Create new utility function for scaling with aspect ratio and use it for DXVA2

app/streaming/streamutils.h

@@ -0,0 +1,10 @@
+#pragma once
+
+#include <SDL.h>
+
+class StreamUtils
+{
+public:
+    static
+    void scaleSourceToDestinationSurface(SDL_Rect* src, SDL_Rect* dst);
+};