Sync with upstream OpenBSD: trivial stuff.

No active ingredient to any of these changes.

Bug: N/A
Test: builds
Change-Id: Ib1191a5c2826da024245d03dfc57557c8903a6cc
diff --git a/libc/upstream-openbsd/lib/libc/gen/vwarnx.c b/libc/upstream-openbsd/lib/libc/gen/vwarnx.c
index 67d8f5b..146e267 100644
--- a/libc/upstream-openbsd/lib/libc/gen/vwarnx.c
+++ b/libc/upstream-openbsd/lib/libc/gen/vwarnx.c
@@ -1,4 +1,4 @@
-/*	$OpenBSD: vwarnx.c,v 1.10 2015/08/31 02:53:57 guenther Exp $ */
+/*	$OpenBSD: vwarnx.c,v 1.11 2016/03/13 18:34:20 guenther Exp $ */
 /*-
  * Copyright (c) 1993
  *	The Regents of the University of California.  All rights reserved.
@@ -30,10 +30,9 @@
 
 #include <err.h>
 #include <stdio.h>
+#include <stdlib.h>
 #include <stdarg.h>
 
-extern char *__progname;		/* Program name, from crt0. */
-
 void
 vwarnx(const char *fmt, va_list ap)
 {