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/root-tree.c b/fs/btrfs/root-tree.c
index 6928bff..59a94c1 100644
--- a/fs/btrfs/root-tree.c
+++ b/fs/btrfs/root-tree.c
@@ -57,7 +57,7 @@
 	btrfs_item_key_to_cpu(path->nodes[0], &search_key, path->slots[0]);
 	if (search_key.type != BTRFS_ROOT_ITEM_KEY) {
 		search_key.offset++;
-		btrfs_release_path(root, path);
+		btrfs_release_path(path);
 		goto again;
 	}
 	ret = 0;
@@ -230,7 +230,7 @@
 
 		memcpy(&found_key, &key, sizeof(key));
 		key.offset++;
-		btrfs_release_path(root, path);
+		btrfs_release_path(path);
 		dead_root =
 			btrfs_read_fs_root_no_radix(root->fs_info->tree_root,
 						    &found_key);
@@ -292,7 +292,7 @@
 		}
 
 		btrfs_item_key_to_cpu(leaf, &key, path->slots[0]);
-		btrfs_release_path(tree_root, path);
+		btrfs_release_path(path);
 
 		if (key.objectid != BTRFS_ORPHAN_OBJECTID ||
 		    key.type != BTRFS_ORPHAN_ITEM_KEY)
@@ -390,7 +390,7 @@
 		err = -ENOENT;
 
 	if (key.type == BTRFS_ROOT_BACKREF_KEY) {
-		btrfs_release_path(tree_root, path);
+		btrfs_release_path(path);
 		key.objectid = ref_id;
 		key.type = BTRFS_ROOT_REF_KEY;
 		key.offset = root_id;
@@ -463,7 +463,7 @@
 	btrfs_mark_buffer_dirty(leaf);
 
 	if (key.type == BTRFS_ROOT_BACKREF_KEY) {
-		btrfs_release_path(tree_root, path);
+		btrfs_release_path(path);
 		key.objectid = ref_id;
 		key.type = BTRFS_ROOT_REF_KEY;
 		key.offset = root_id;