Use GetRawInputBuffer() instead processing raw input one at a time

This is a huge performance improvement for high polling rate mice, like the Razer Viper 8K mouse.

Fixes https://github.com/libsdl-org/SDL/issues/8756

src/video/windows/SDL_windowswindow.c

@@ -518,6 +518,7 @@ static void CleanupWindowData(SDL_VideoDevice *_this, SDL_Window *window)
 #endif
             }
         }
+        SDL_free(data->rawinput);
         SDL_free(data);
     }
     window->driverdata = NULL;