[PATCH] turn many #if $undefined_string into #ifdef $undefined_string

turn many #if $undefined_string into #ifdef $undefined_string to fix some
warnings after -Wno-def was added to global CFLAGS

Signed-off-by: Olaf Hering <olh@suse.de>
Signed-off-by: Andrew Morton <akpm@osdl.org>
Signed-off-by: Linus Torvalds <torvalds@osdl.org>
diff --git a/drivers/cdrom/mcdx.c b/drivers/cdrom/mcdx.c
index 07bbd24..b89420e 100644
--- a/drivers/cdrom/mcdx.c
+++ b/drivers/cdrom/mcdx.c
@@ -51,7 +51,7 @@
  */
 
 
-#if RCS
+#ifdef RCS
 static const char *mcdx_c_version
     = "$Id: mcdx.c,v 1.21 1997/01/26 07:12:59 davem Exp $";
 #endif
@@ -706,7 +706,7 @@
 		xtrace(OPENCLOSE, "open() init irq generation\n");
 		if (-1 == mcdx_config(stuffp, 1))
 			return -EIO;
-#if FALLBACK
+#ifdef FALLBACK
 		/* Set the read speed */
 		xwarn("AAA %x AAA\n", stuffp->readcmd);
 		if (stuffp->readerrs)
@@ -1216,7 +1216,7 @@
 	}
 
 
-#if WE_KNOW_WHY
+#ifdef WE_KNOW_WHY
 	/* irq 11 -> channel register */
 	outb(0x50, stuffp->wreg_chn);
 #endif
@@ -1294,7 +1294,7 @@
 
 	ans = mcdx_xfer(stuffp, p, sector, nr_sectors);
 	return ans;
-#if FALLBACK
+#ifdef FALLBACK
 	if (-1 == ans)
 		stuffp->readerrs++;
 	else