[5.2] d70fe1f Missing header

[PÃ¥l Hermunn Johansen]

commit d70fe1fc10bf7173f364a85261bf19d16f5d82ea
Author: Dridi Boukelmoune <dridi.boukelmoune at gmail.com>
Date:   Thu Sep 14 01:07:51 2017 +0200

    Missing header

diff --git a/bin/varnishlog/varnishlog.c b/bin/varnishlog/varnishlog.c
index bc0c352..e0a4846 100644
--- a/bin/varnishlog/varnishlog.c
+++ b/bin/varnishlog/varnishlog.c
@@ -32,6 +32,7 @@
 
 #include "config.h"
 
+#include <stdarg.h>
 #include <stdlib.h>
 #include <stdio.h>
 #include <unistd.h>