remove "struct subsystem" as it is no longer needed

We need to work on cleaning up the relationship between kobjects, ksets and
ktypes.  The removal of 'struct subsystem' is the first step of this,
especially as it is not really needed at all.

Thanks to Kay for fixing the bugs in this patch.

Signed-off-by: Greg Kroah-Hartman <gregkh@suse.de>

diff --git a/block/genhd.c b/block/genhd.c
index 441432a..b566444 100644
--- a/block/genhd.c
+++ b/block/genhd.c
@@ -17,7 +17,7 @@
 #include <linux/buffer_head.h>
 #include <linux/mutex.h>
 
-struct subsystem block_subsys;
+struct kset block_subsys;
 static DEFINE_MUTEX(block_subsys_lock);
 
 /*
@@ -221,7 +221,7 @@
 	loff_t l = *pos;
 
 	mutex_lock(&block_subsys_lock);
-	list_for_each(p, &block_subsys.kset.list)
+	list_for_each(p, &block_subsys.list)
 		if (!l--)
 			return list_entry(p, struct gendisk, kobj.entry);
 	return NULL;
@@ -231,7 +231,7 @@
 {
 	struct list_head *p = ((struct gendisk *)v)->kobj.entry.next;
 	++*pos;
-	return p==&block_subsys.kset.list ? NULL : 
+	return p==&block_subsys.list ? NULL :
 		list_entry(p, struct gendisk, kobj.entry);
 }
 
@@ -246,7 +246,7 @@
 	int n;
 	char buf[BDEVNAME_SIZE];
 
-	if (&sgp->kobj.entry == block_subsys.kset.list.next)
+	if (&sgp->kobj.entry == block_subsys.list.next)
 		seq_puts(part, "major minor  #blocks  name\n\n");
 
 	/* Don't show non-partitionable removeable devices or empty devices */
@@ -565,7 +565,7 @@
 	struct list_head *p;
 
 	mutex_lock(&block_subsys_lock);
-	list_for_each(p, &block_subsys.kset.list)
+	list_for_each(p, &block_subsys.list)
 		if (!k--)
 			return list_entry(p, struct gendisk, kobj.entry);
 	return NULL;
@@ -575,7 +575,7 @@
 {
 	struct list_head *p = ((struct gendisk *)v)->kobj.entry.next;
 	++*pos;
-	return p==&block_subsys.kset.list ? NULL :
+	return p==&block_subsys.list ? NULL :
 		list_entry(p, struct gendisk, kobj.entry);
 }