SDL: Run EGL/GLES cmake tests with the Khronos headers available

From 116c60c5b039774ff56444aafe45a14572c3bea3 Mon Sep 17 00:00:00 2001
From: Sam Lantinga <[EMAIL REDACTED]>
Date: Fri, 19 Jan 2024 22:31:15 -0800
Subject: [PATCH] Run EGL/GLES cmake tests with the Khronos headers available

---
 CMakeLists.txt | 1 +
 1 file changed, 1 insertion(+)

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 5985005551fa..5d116812f5e0 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -448,6 +448,7 @@ if(USE_GCC OR USE_INTELCC OR (USE_CLANG AND NOT MSVC_CLANG))
 else()
   sdl_include_directories(NO_EXPORT SYSTEM PUBLIC "$<BUILD_INTERFACE:${SDL3_SOURCE_DIR}/src/video/khronos>")
 endif()
+list(APPEND CMAKE_REQUIRED_INCLUDES "${SDL3_SOURCE_DIR}/src/video/khronos")
 
 # General source files
 sdl_glob_sources(