btrfs: btrfs_abort_transaction, drop root parameter

__btrfs_abort_transaction doesn't use its root parameter except to
obtain an fs_info pointer.  We can obtain that from trans->root->fs_info
for now and from trans->fs_info in a later patch.

Signed-off-by: Jeff Mahoney <jeffm@suse.com>
Signed-off-by: David Sterba <dsterba@suse.com>
diff --git a/fs/btrfs/delayed-inode.c b/fs/btrfs/delayed-inode.c
index 9e2a907..3eeb9cd 100644
--- a/fs/btrfs/delayed-inode.c
+++ b/fs/btrfs/delayed-inode.c
@@ -1170,7 +1170,7 @@
 		if (ret) {
 			btrfs_release_delayed_node(curr_node);
 			curr_node = NULL;
-			btrfs_abort_transaction(trans, root, ret);
+			btrfs_abort_transaction(trans, ret);
 			break;
 		}