Windows: Fix other window positions/sizes being changed when exiting exclusive fullscreen (bug #3315, thanks Simon Hug!)

src/video/windows/SDL_windowsmodes.c

@@ -416,7 +416,7 @@ WIN_SetDisplayMode(_THIS, SDL_VideoDisplay * display, SDL_DisplayMode * mode)
     LONG status;
 
     if (mode->driverdata == display->desktop_mode.driverdata) {
-        status = ChangeDisplaySettingsEx(displaydata->DeviceName, NULL, NULL, 0, NULL);
+        status = ChangeDisplaySettingsEx(displaydata->DeviceName, NULL, NULL, CDS_FULLSCREEN, NULL);
     } else {
         status = ChangeDisplaySettingsEx(displaydata->DeviceName, &data->DeviceMode, NULL, CDS_FULLSCREEN, NULL);
     }