kill an unused PTR_ERR in bdev_cache_init()

Signed-off-by: Qi Yong <qiyong@fc-cn.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/fs/block_dev.c b/fs/block_dev.c
index e48a630..e63067d 100644
--- a/fs/block_dev.c
+++ b/fs/block_dev.c
@@ -534,7 +534,6 @@
 	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 */