Update to FreeBSD head 2018-02-01

Git mirror commit d079ae0442af8fa3cfd6d7ede190d04e64a2c0d4.

Update #3472.

freebsd/lib/libc/net/if_indextoname.c

@@ -3,6 +3,8 @@
 /*	$KAME: if_indextoname.c,v 1.7 2000/11/08 03:09:30 itojun Exp $	*/
 
 /*-
+ * SPDX-License-Identifier: BSD-1-Clause
+ *
  * Copyright (c) 1997, 2000
  *	Berkeley Software Design, Inc.  All rights reserved.
  *