fs/super.c: fix WARN on alloc_super() fail path

On fail path alloc_super() calls destroy_super(), which issues a warning
if the sb's s_mounts list is not empty, in particular if it has not been
initialized.  That said s_mounts must be initialized in alloc_super()
before any possible failure, but currently it is initialized close to
the end of the function leading to a useless warning dumped to log if
either percpu_counter_init() or list_lru_init() fails.  Let's fix this.
Signed-off-by: NVladimir Davydov <vdavydov@parallels.com>
Cc: Al Viro <viro@zeniv.linux.org.uk>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

fs/super.c

@@ -166,6 +166,8 @@ static struct super_block *alloc_super(struct file_system_type *type, int flags)
 	if (!s)
 		return NULL;
 
+	INIT_LIST_HEAD(&s->s_mounts);
+
 	if (security_sb_alloc(s))
 		goto fail;
 
@@ -188,7 +190,6 @@ static struct super_block *alloc_super(struct file_system_type *type, int flags)
 	if (list_lru_init(&s->s_inode_lru))
 		goto fail;
 
-	INIT_LIST_HEAD(&s->s_mounts);
 	init_rwsem(&s->s_umount);
 	lockdep_set_class(&s->s_umount, &type->s_umount_key);
 	/*