Revert "ubifs: Fix memory leak bug in alloc_ubifs_info() error path"

This reverts commit 9163e01.

At the point when ubifs_fill_super() runs, we have already a reference
to the super block. So upon deactivate_locked_super() c will get
free()'ed via ->kill_sb().

Cc: Wenwen Wang <wenwen@cs.uga.edu>
Fixes: 9163e01 ("ubifs: Fix memory leak bug in alloc_ubifs_info() error path")
Reported-by: https://twitter.com/grsecurity/status/1180609139359277056
Signed-off-by: Richard Weinberger <richard@nod.at>
Tested-by: Romain Izard <romain.izard.pro@gmail.com>
Signed-off-by: Richard Weinberger <richard@nod.at>

fs/ubifs/super.c

@@ -2267,10 +2267,8 @@ static struct dentry *ubifs_mount(struct file_system_type *fs_type, int flags,
 		}
 	} else {
 		err = ubifs_fill_super(sb, data, flags & SB_SILENT ? 1 : 0);
-		if (err) {
-			kfree(c);
+		if (err)
 			goto out_deact;
-		}
 		/* We do not support atime */
 		sb->s_flags |= SB_ACTIVE;
 		if (IS_ENABLED(CONFIG_UBIFS_ATIME_SUPPORT))