btrfs: fix an error handling path in btrfs_rename()

If new_whiteout_inode() fails, some resources need to be freed.
Add the missing goto to the error handling path.

Fixes: ab3c5c18e8 ("btrfs: setup qstr from dentrys using fscrypt helper")
Reviewed-by: Sweet Tea Dorminy <sweettea-kernel@dorminy.me>
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: David Sterba <dsterba@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>

fs/btrfs/inode.c

@@ -9377,8 +9377,10 @@ static int btrfs_rename(struct user_namespace *mnt_userns,
 
 	if (flags & RENAME_WHITEOUT) {
 		whiteout_args.inode = new_whiteout_inode(mnt_userns, old_dir);
-		if (!whiteout_args.inode)
-			return -ENOMEM;
+		if (!whiteout_args.inode) {
+			ret = -ENOMEM;
+			goto out_fscrypt_names;
+		}
 		ret = btrfs_new_inode_prepare(&whiteout_args, &trans_num_items);
 		if (ret)
 			goto out_whiteout_inode;