sdl2-compat: test/testgles2_sdf.c uses functions in testutils.h

SDL Commits
1 
From 4cceda4d05f724ba35497882faa906b808402920 Mon Sep 17 00:00:00 2001
From: Anonymous Maarten <[EMAIL REDACTED]>
Date: Tue, 29 Nov 2022 17:30:11 +0100
Subject: [PATCH] test/testgles2_sdf.c uses functions in testutils.h

---
 test/testgles2_sdf.c | 1 +
 1 file changed, 1 insertion(+)

diff --git a/test/testgles2_sdf.c b/test/testgles2_sdf.c
index 3373941..1386d55 100644
--- a/test/testgles2_sdf.c
+++ b/test/testgles2_sdf.c
@@ -19,6 +19,7 @@
 #endif
 
 #include "SDL_test_common.h"
+#include "testutils.h"
 
 #if defined(__IPHONEOS__) || defined(__ANDROID__) || defined(__EMSCRIPTEN__) || defined(__NACL__) \
     || defined(__WINDOWS__) || defined(__LINUX__)