fat: remove unnecessary dentry_unhash on rmdir, dir rename

fat does not have problems with references to unlinked directories.

CC: OGAWA Hirofumi <hirofumi@mail.parknet.co.jp>
Signed-off-by: Sage Weil <sage@newdream.net>
Signed-off-by: Al Viro <viro@zeniv.linux.org.uk>
diff --git a/fs/fat/namei_msdos.c b/fs/fat/namei_msdos.c
index be15437..3b222da 100644
--- a/fs/fat/namei_msdos.c
+++ b/fs/fat/namei_msdos.c
@@ -326,8 +326,6 @@
 	struct fat_slot_info sinfo;
 	int err;
 
-	dentry_unhash(dentry);
-
 	lock_super(sb);
 	/*
 	 * Check whether the directory is not in use, then check
@@ -459,9 +457,6 @@
 	old_inode = old_dentry->d_inode;
 	new_inode = new_dentry->d_inode;
 
-	if (new_inode && S_ISDIR(new_inode->i_mode))
-		dentry_unhash(new_dentry);
-
 	err = fat_scan(old_dir, old_name, &old_sinfo);
 	if (err) {
 		err = -EIO;
diff --git a/fs/fat/namei_vfat.c b/fs/fat/namei_vfat.c
index c61a678..20b4ea5 100644
--- a/fs/fat/namei_vfat.c
+++ b/fs/fat/namei_vfat.c
@@ -824,8 +824,6 @@
 	struct fat_slot_info sinfo;
 	int err;
 
-	dentry_unhash(dentry);
-
 	lock_super(sb);
 
 	err = fat_dir_empty(inode);
@@ -933,9 +931,6 @@
 	int err, is_dir, update_dotdot, corrupt = 0;
 	struct super_block *sb = old_dir->i_sb;
 
-	if (new_dentry->d_inode && S_ISDIR(new_dentry->d_inode->i_mode))
-		dentry_unhash(new_dentry);
-
 	old_sinfo.bh = sinfo.bh = dotdot_bh = NULL;
 	old_inode = old_dentry->d_inode;
 	new_inode = new_dentry->d_inode;