libobs-opengl: Add warning when used on windows

libobs-opengl/gl-subsystem.c

@@ -221,6 +221,14 @@ int device_create(gs_device_t **p_device, uint32_t adapter)
 	device_leave_context(device);
 	device->cur_swap = NULL;
 
+#ifdef _WIN32
+	blog(LOG_INFO, "Warning: The OpenGL renderer is currently in use.  "
+			"On windows, the OpenGL renderer can decrease "
+			"capture performance due to the lack of specific "
+			"features used to maximize capture performance.  "
+			"The Direct3D 11 renderer is recommended instead.");
+#endif
+
 	*p_device = device;
 	return GS_SUCCESS;