[libdazzle] util: add string.h for strlen

[Christian Hergert <chergert src gnome org>]

commit 74fc48cdb43d124ed29a99ece865d9922ea9634c
Author: Christian Hergert <chergert redhat com>
Date:   Sun Nov 26 15:54:15 2017 -0800

    util: add string.h for strlen

 src/util/dzl-macros.h |    1 +
 1 files changed, 1 insertions(+), 0 deletions(-)
---
diff --git a/src/util/dzl-macros.h b/src/util/dzl-macros.h
index 070c9a5..b352317 100644
--- a/src/util/dzl-macros.h
+++ b/src/util/dzl-macros.h
@@ -20,6 +20,7 @@
 #define DZL_MACROS_H
 
 #include <glib.h>
+#include <string.h>
 
 G_BEGIN_DECLS