Add <stdarg.h> include

git-svn-id: http://www.varnish-cache.org/svn/trunk/varnish-cache@601 d4fa192b-c00b-0410-8231-f00ffab90ce4

bin/varnishd/cache_http.c

@@ -7,6 +7,7 @@
 #include <stdio.h>
 #include <errno.h>
 #include <unistd.h>
+#include <stdarg.h>
 #include <stdlib.h>
 #include <string.h>
 #include <ctype.h>