Fix proper release of swap chain

git-svn-id: svn://svn.code.sf.net/p/irrlicht/code/trunk@4091 dfc29bdd-3216-0410-991c-e03cc46cb475

source/Irrlicht/CD3D9Driver.cpp

@@ -593,6 +593,7 @@ bool CD3D9Driver::endScene()
 	hr = pID3DDevice->GetSwapChain(0, &swChain);
 	DWORD flags = (Params.HandleSRGB && (Caps.Caps3&D3DCAPS3_LINEAR_TO_SRGB_PRESENTATION))?D3DPRESENT_LINEAR_CONTENT:0;
 	hr = swChain->Present(srcRct, NULL, WindowId, NULL, flags);
+	swChain->Release();
 
 	if (SUCCEEDED(hr))
 		return true;