btrfs: drop unused parameter from btrfs_release_path

parameter tree root it's not used since commit
5f39d397dfbe140a14edecd4e73c34ce23c4f9ee ("Btrfs: Create extent_buffer
interface for large blocksizes")

Signed-off-by: David Sterba <dsterba@suse.cz>
diff --git a/fs/btrfs/xattr.c b/fs/btrfs/xattr.c
index cfd6605..4ca88d1 100644
--- a/fs/btrfs/xattr.c
+++ b/fs/btrfs/xattr.c
@@ -120,13 +120,13 @@
 
 		ret = btrfs_delete_one_dir_name(trans, root, path, di);
 		BUG_ON(ret);
-		btrfs_release_path(root, path);
+		btrfs_release_path(path);
 
 		/* if we don't have a value then we are removing the xattr */
 		if (!value)
 			goto out;
 	} else {
-		btrfs_release_path(root, path);
+		btrfs_release_path(path);
 
 		if (flags & XATTR_REPLACE) {
 			/* we couldn't find the attr to replace */