sysfs: kill sysfs_sb declaration in fs/sysfs/inode.c.

This patch removes sysfs_sb declaration from fs/sysfs/inode.c
(due to 0f4288ec6fcc1a47d1fa0241ec1c6dacd5a09e96,
 "Kill unused sysfs_sb variable").

Signed-off-by: Rami Rosen <ramirose@gmail.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>

fs/sysfs/inode.c

@@ -24,8 +24,6 @@
 #include <linux/security.h>
 #include "sysfs.h"
 
-extern struct super_block * sysfs_sb;
-
 static const struct address_space_operations sysfs_aops = {
 	.readpage	= simple_readpage,
 	.write_begin	= simple_write_begin,