Fix bug 3081: CMake configuration auto-disables OpenGL ES support on Windows.

Thanks to EntranceJew for the patch.

CMakeLists.txt

@@ -1027,6 +1027,13 @@ elseif(WINDOWS)
       set(SDL_VIDEO_RENDER_OGL 1)
       set(HAVE_VIDEO_OPENGL TRUE)
     endif()
+
+    if(VIDEO_OPENGLES)
+      set(SDL_VIDEO_OPENGL_EGL 1)
+      set(SDL_VIDEO_OPENGL_ES2 1)
+      set(SDL_VIDEO_RENDER_OGL_ES2 1)
+      set(HAVE_VIDEO_OPENGLES TRUE)
+    endif()
   endif()
 
   if(SDL_JOYSTICK)