tree-wide: convert open calls to remove spaces to skip_spaces() lib function

Makes use of skip_spaces() defined in lib/string.c for removing leading
spaces from strings all over the tree.

It decreases lib.a code size by 47 bytes and reuses the function tree-wide:
   text    data     bss     dec     hex filename
  64688     584     592   65864   10148 (TOTALS-BEFORE)
  64641     584     592   65817   10119 (TOTALS-AFTER)

Also, while at it, if we see (*str && isspace(*str)), we can be sure to
remove the first condition (*str) as the second one (isspace(*str)) also
evaluates to 0 whenever *str == 0, making it redundant. In other words,
"a char equals zero is never a space".

Julia Lawall tried the semantic patch (http://coccinelle.lip6.fr) below,
and found occurrences of this pattern on 3 more files:
    drivers/leds/led-class.c
    drivers/leds/ledtrig-timer.c
    drivers/video/output.c

@@
expression str;
@@

( // ignore skip_spaces cases
while (*str &&  isspace(*str)) { \(str++;\|++str;\) }
|
- *str &&
isspace(*str)
)

Signed-off-by: André Goddard Rosa <andre.goddard@gmail.com>
Cc: Julia Lawall <julia@diku.dk>
Cc: Martin Schwidefsky <schwidefsky@de.ibm.com>
Cc: Jeff Dike <jdike@addtoit.com>
Cc: Ingo Molnar <mingo@elte.hu>
Cc: Thomas Gleixner <tglx@linutronix.de>
Cc: "H. Peter Anvin" <hpa@zytor.com>
Cc: Richard Purdie <rpurdie@rpsys.net>
Cc: Neil Brown <neilb@suse.de>
Cc: Kyle McMartin <kyle@mcmartin.ca>
Cc: Henrique de Moraes Holschuh <hmh@hmh.eng.br>
Cc: David Howells <dhowells@redhat.com>
Cc: <linux-ext4@vger.kernel.org>
Cc: Samuel Ortiz <samuel@sortiz.org>
Cc: Patrick McHardy <kaber@trash.net>
Cc: Takashi Iwai <tiwai@suse.de>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/leds/led-class.c b/drivers/leds/led-class.c
index f2cc13d..782f958 100644
--- a/drivers/leds/led-class.c
+++ b/drivers/leds/led-class.c
@@ -50,7 +50,7 @@
 	unsigned long state = simple_strtoul(buf, &after, 10);
 	size_t count = after - buf;
 
-	if (*after && isspace(*after))
+	if (isspace(*after))
 		count++;
 
 	if (count == size) {
diff --git a/drivers/leds/ledtrig-timer.c b/drivers/leds/ledtrig-timer.c
index 3b83406..38b3378 100644
--- a/drivers/leds/ledtrig-timer.c
+++ b/drivers/leds/ledtrig-timer.c
@@ -83,7 +83,7 @@
 	unsigned long state = simple_strtoul(buf, &after, 10);
 	size_t count = after - buf;
 
-	if (*after && isspace(*after))
+	if (isspace(*after))
 		count++;
 
 	if (count == size) {
@@ -127,7 +127,7 @@
 	unsigned long state = simple_strtoul(buf, &after, 10);
 	size_t count = after - buf;
 
-	if (*after && isspace(*after))
+	if (isspace(*after))
 		count++;
 
 	if (count == size) {
diff --git a/drivers/md/dm-table.c b/drivers/md/dm-table.c
index 1a6cb3c..91976e8 100644
--- a/drivers/md/dm-table.c
+++ b/drivers/md/dm-table.c
@@ -12,6 +12,7 @@
 #include <linux/blkdev.h>
 #include <linux/namei.h>
 #include <linux/ctype.h>
+#include <linux/string.h>
 #include <linux/slab.h>
 #include <linux/interrupt.h>
 #include <linux/mutex.h>
@@ -600,11 +601,8 @@
 		return -ENOMEM;
 
 	while (1) {
-		start = end;
-
 		/* Skip whitespace */
-		while (*start && isspace(*start))
-			start++;
+		start = skip_spaces(end);
 
 		if (!*start)
 			break;	/* success, we hit the end */
diff --git a/drivers/md/md.c b/drivers/md/md.c
index e1f3c17..6f91486 100644
--- a/drivers/md/md.c
+++ b/drivers/md/md.c
@@ -39,6 +39,7 @@
 #include <linux/buffer_head.h> /* for invalidate_bdev */
 #include <linux/poll.h>
 #include <linux/ctype.h>
+#include <linux/string.h>
 #include <linux/hdreg.h>
 #include <linux/proc_fs.h>
 #include <linux/random.h>
@@ -3439,8 +3440,7 @@
 		}
 		if (*end && !isspace(*end)) break;
 		bitmap_dirty_bits(mddev->bitmap, chunk, end_chunk);
-		buf = end;
-		while (isspace(*buf)) buf++;
+		buf = skip_spaces(end);
 	}
 	bitmap_unplug(mddev->bitmap); /* flush the bits to disk */
 out:
diff --git a/drivers/parisc/pdc_stable.c b/drivers/parisc/pdc_stable.c
index 13a64bc..0bc5d47 100644
--- a/drivers/parisc/pdc_stable.c
+++ b/drivers/parisc/pdc_stable.c
@@ -779,12 +779,9 @@
 	read_unlock(&pathentry->rw_lock);
 	
 	DPRINTK("%s: flags before: 0x%X\n", __func__, flags);
-			
-	temp = in;
-	
-	while (*temp && isspace(*temp))
-		temp++;
-	
+
+	temp = skip_spaces(in);
+
 	c = *temp++ - '0';
 	if ((c != 0) && (c != 1))
 		goto parse_error;
diff --git a/drivers/platform/x86/thinkpad_acpi.c b/drivers/platform/x86/thinkpad_acpi.c
index 0ed8480..cf61d6a 100644
--- a/drivers/platform/x86/thinkpad_acpi.c
+++ b/drivers/platform/x86/thinkpad_acpi.c
@@ -1006,11 +1006,8 @@
 {
 	char *endp;
 
-	while (*buf && isspace(*buf))
-		buf++;
-	*value = simple_strtoul(buf, &endp, 0);
-	while (*endp && isspace(*endp))
-		endp++;
+	*value = simple_strtoul(skip_spaces(buf), &endp, 0);
+	endp = skip_spaces(endp);
 	if (*endp || *value > max)
 		return -EINVAL;
 
diff --git a/drivers/pnp/interface.c b/drivers/pnp/interface.c
index c3f1c8e..68b0c04 100644
--- a/drivers/pnp/interface.c
+++ b/drivers/pnp/interface.c
@@ -310,8 +310,7 @@
 		goto done;
 	}
 
-	while (isspace(*buf))
-		++buf;
+	buf = skip_spaces(buf);
 	if (!strnicmp(buf, "disable", 7)) {
 		retval = pnp_disable_dev(dev);
 		goto done;
@@ -353,19 +352,13 @@
 		pnp_init_resources(dev);
 		mutex_lock(&pnp_res_mutex);
 		while (1) {
-			while (isspace(*buf))
-				++buf;
+			buf = skip_spaces(buf);
 			if (!strnicmp(buf, "io", 2)) {
-				buf += 2;
-				while (isspace(*buf))
-					++buf;
+				buf = skip_spaces(buf + 2);
 				start = simple_strtoul(buf, &buf, 0);
-				while (isspace(*buf))
-					++buf;
+				buf = skip_spaces(buf);
 				if (*buf == '-') {
-					buf += 1;
-					while (isspace(*buf))
-						++buf;
+					buf = skip_spaces(buf + 1);
 					end = simple_strtoul(buf, &buf, 0);
 				} else
 					end = start;
@@ -373,16 +366,11 @@
 				continue;
 			}
 			if (!strnicmp(buf, "mem", 3)) {
-				buf += 3;
-				while (isspace(*buf))
-					++buf;
+				buf = skip_spaces(buf + 3);
 				start = simple_strtoul(buf, &buf, 0);
-				while (isspace(*buf))
-					++buf;
+				buf = skip_spaces(buf);
 				if (*buf == '-') {
-					buf += 1;
-					while (isspace(*buf))
-						++buf;
+					buf = skip_spaces(buf + 1);
 					end = simple_strtoul(buf, &buf, 0);
 				} else
 					end = start;
@@ -390,17 +378,13 @@
 				continue;
 			}
 			if (!strnicmp(buf, "irq", 3)) {
-				buf += 3;
-				while (isspace(*buf))
-					++buf;
+				buf = skip_spaces(buf + 3);
 				start = simple_strtoul(buf, &buf, 0);
 				pnp_add_irq_resource(dev, start, 0);
 				continue;
 			}
 			if (!strnicmp(buf, "dma", 3)) {
-				buf += 3;
-				while (isspace(*buf))
-					++buf;
+				buf = skip_spaces(buf + 3);
 				start = simple_strtoul(buf, &buf, 0);
 				pnp_add_dma_resource(dev, start, 0);
 				continue;
diff --git a/drivers/s390/block/dasd_proc.c b/drivers/s390/block/dasd_proc.c
index 5f23eca..6315fbd 100644
--- a/drivers/s390/block/dasd_proc.c
+++ b/drivers/s390/block/dasd_proc.c
@@ -14,6 +14,7 @@
 #define KMSG_COMPONENT "dasd"
 
 #include <linux/ctype.h>
+#include <linux/string.h>
 #include <linux/seq_file.h>
 #include <linux/vmalloc.h>
 #include <linux/proc_fs.h>
@@ -272,10 +273,10 @@
 	DBF_EVENT(DBF_DEBUG, "/proc/dasd/statictics: '%s'\n", buffer);
 
 	/* check for valid verbs */
-	for (str = buffer; isspace(*str); str++);
+	str = skip_spaces(buffer);
 	if (strncmp(str, "set", 3) == 0 && isspace(str[3])) {
 		/* 'set xxx' was given */
-		for (str = str + 4; isspace(*str); str++);
+		str = skip_spaces(str + 4);
 		if (strcmp(str, "on") == 0) {
 			/* switch on statistics profiling */
 			dasd_profile_level = DASD_PROFILE_ON;
diff --git a/drivers/video/backlight/lcd.c b/drivers/video/backlight/lcd.c
index a482dd7..9b3be74 100644
--- a/drivers/video/backlight/lcd.c
+++ b/drivers/video/backlight/lcd.c
@@ -101,7 +101,7 @@
 	int power = simple_strtoul(buf, &endp, 0);
 	size_t size = endp - buf;
 
-	if (*endp && isspace(*endp))
+	if (isspace(*endp))
 		size++;
 	if (size != count)
 		return -EINVAL;
@@ -140,7 +140,7 @@
 	int contrast = simple_strtoul(buf, &endp, 0);
 	size_t size = endp - buf;
 
-	if (*endp && isspace(*endp))
+	if (isspace(*endp))
 		size++;
 	if (size != count)
 		return -EINVAL;
diff --git a/drivers/video/display/display-sysfs.c b/drivers/video/display/display-sysfs.c
index 4830b1b..80abbf3 100644
--- a/drivers/video/display/display-sysfs.c
+++ b/drivers/video/display/display-sysfs.c
@@ -67,7 +67,7 @@
 	contrast = simple_strtoul(buf, &endp, 0);
 	size = endp - buf;
 
-	if (*endp && isspace(*endp))
+	if (isspace(*endp))
 		size++;
 
 	if (size != count)
diff --git a/drivers/video/output.c b/drivers/video/output.c
index 5e6439a..5137aa0 100644
--- a/drivers/video/output.c
+++ b/drivers/video/output.c
@@ -50,7 +50,7 @@
 	int request_state = simple_strtoul(buf,&endp,0);
 	size_t size = endp - buf;
 
-	if (*endp && isspace(*endp))
+	if (isspace(*endp))
 		size++;
 	if (size != count)
 		return -EINVAL;