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/inode.c b/fs/btrfs/inode.c
index ca405171..d65a55c 100644
--- a/fs/btrfs/inode.c
+++ b/fs/btrfs/inode.c
@@ -4178,8 +4178,7 @@
 				}
 				size =
 				    btrfs_file_extent_calc_inline_size(size);
-				btrfs_truncate_item(trans, root, path,
-						    size, 1);
+				btrfs_truncate_item(root, path, size, 1);
 			} else if (root->ref_cows) {
 				inode_sub_bytes(inode, item_end + 1 -
 						found_key.offset);