Add GPU to iOS build config

include/build_config/SDL_build_config_ios.h

@@ -196,16 +196,13 @@
 #define SDL_PLATFORM_SUPPORTS_METAL 0
 #endif
 
-#if SDL_PLATFORM_SUPPORTS_METAL
-#define SDL_VIDEO_RENDER_METAL  1
-#endif
-
-#if SDL_PLATFORM_SUPPORTS_METAL
-#define SDL_VIDEO_VULKAN 1
-#endif
-
 #if SDL_PLATFORM_SUPPORTS_METAL
 #define SDL_VIDEO_METAL 1
+#define SDL_GPU_METAL 1
+#define SDL_VIDEO_RENDER_METAL 1
+#define SDL_VIDEO_VULKAN 1
+#define SDL_GPU_VULKAN 1
+#define SDL_VIDEO_RENDER_GPU  1
 #endif
 
 /* Enable system power support */