updae source to 2.0.9 source

Edward Rudd

2019-04-09 9cd2e9ec8fc0127393dfce9c0359d500c8c238be

 source/src/audio/wasapi/SDL_wasapi.c

@@ -725,6 +725,12 @@
    WASAPI_PlatformThreadDeinit(this);
}

void
WASAPI_BeginLoopIteration(_THIS)
{
   /* no-op. */
}

static void
WASAPI_Deinitialize(void)
{