Btrfs: remove unused argument of btrfs_extend_item()

Argument 'trans' is not used in btrfs_extend_item().

Signed-off-by: Tsutomu Itoh <t-itoh@jp.fujitsu.com>
Signed-off-by: Josef Bacik <jbacik@fusionio.com>
diff --git a/fs/btrfs/ctree.c b/fs/btrfs/ctree.c
index 01a8a3b..566d99b 100644
--- a/fs/btrfs/ctree.c
+++ b/fs/btrfs/ctree.c
@@ -4383,8 +4383,7 @@
 /*
  * make the item pointed to by the path bigger, data_size is the new size.
  */
-void btrfs_extend_item(struct btrfs_trans_handle *trans,
-		       struct btrfs_root *root, struct btrfs_path *path,
+void btrfs_extend_item(struct btrfs_root *root, struct btrfs_path *path,
 		       u32 data_size)
 {
 	int slot;