Btrfs: remove path arg from btrfs_truncate_free_space_cache

Not used for anything, and removing it avoids caller's need to
allocate a path structure.

Signed-off-by: Filipe David Borba Manana <fdmanana@gmail.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
Signed-off-by: Chris Mason <chris.mason@fusionio.com>
diff --git a/fs/btrfs/extent-tree.c b/fs/btrfs/extent-tree.c
index d58bef1..55b537f 100644
--- a/fs/btrfs/extent-tree.c
+++ b/fs/btrfs/extent-tree.c
@@ -3197,8 +3197,7 @@
 		if (ret)
 			goto out_put;
 
-		ret = btrfs_truncate_free_space_cache(root, trans, path,
-						      inode);
+		ret = btrfs_truncate_free_space_cache(root, trans, inode);
 		if (ret)
 			goto out_put;
 	}