Avoid problems with Intel drivers when passing 0 as HDc, calls are equivalent when context is 0.

git-svn-id: svn://svn.code.sf.net/p/irrlicht/code/trunk@4161 dfc29bdd-3216-0410-991c-e03cc46cb475

source/Irrlicht/COpenGLDriver.cpp

@@ -635,7 +635,7 @@ COpenGLDriver::~COpenGLDriver()
 
 		if (ExposedData.OpenGLWin32.HRc)
 		{
-			if (!wglMakeCurrent(0, 0))
+			if (!wglMakeCurrent(HDc, 0))
 				os::Printer::log("Release of dc and rc failed.", ELL_WARNING);
 
 			if (!wglDeleteContext((HGLRC)ExposedData.OpenGLWin32.HRc))