Btrfs: cleanup of function where fixup_low_keys() is called

If argument 'trans' is unnecessary in the function where
fixup_low_keys() is called, 'trans' is deleted.

Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
diff --git a/fs/btrfs/tree-log.c b/fs/btrfs/tree-log.c
index b069faf..3442dd9 100644
--- a/fs/btrfs/tree-log.c
+++ b/fs/btrfs/tree-log.c
@@ -408,7 +408,7 @@
 		found_size = btrfs_item_size_nr(path->nodes[0],
 						path->slots[0]);
 		if (found_size > item_size)
-			btrfs_truncate_item(trans, root, path, item_size, 1);
+			btrfs_truncate_item(root, path, item_size, 1);
 		else if (found_size < item_size)
 			btrfs_extend_item(trans, root, path,
 					  item_size - found_size);