tests: Include "config.h" as first header

Signed-off-by: Bryce Harrington <bryce@osg.samsung.com>
diff --git a/tests/xwayland-test.c b/tests/xwayland-test.c
index 658453f..e94e8f5 100644
--- a/tests/xwayland-test.c
+++ b/tests/xwayland-test.c
@@ -25,7 +25,7 @@
  * general works with Weston.
  */
 
-#include "weston-test-runner.h"
+#include "config.h"
 
 #include <assert.h>
 #include <unistd.h>
@@ -37,6 +37,8 @@
 #include <xcb/dri2.h>
 #include <xf86drm.h>
 
+#include "weston-test-runner.h"
+
 
 static int
 dri2_open(xcb_connection_t *c, xcb_screen_t *screen)