kill an unused PTR_ERR in bdev_cache_init()

Signed-off-by: NQi Yong <qiyong@fc-cn.com>
Signed-off-by: NAndrew Morton <akpm@linux-foundation.org>
Signed-off-by: NLinus Torvalds <torvalds@linux-foundation.org>

fs/block_dev.c

@@ -534,7 +534,6 @@ void __init bdev_cache_init(void)
 	if (err)
 		panic("Cannot register bdev pseudo-fs");
 	bd_mnt = kern_mount(&bd_type);
-	err = PTR_ERR(bd_mnt);
 	if (IS_ERR(bd_mnt))
 		panic("Cannot create bdev pseudo-fs");
 	blockdev_superblock = bd_mnt->mnt_sb;	/* For writeback */