Fix cast from "void*" to integer type in wxThread::Exit() for non-MSVC.

This fixes another problem in 64 bit Cygwin build.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@76507 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/msw/thread.cpp

@@ -1196,7 +1196,7 @@ void wxThread::Exit(ExitCode status)
 #ifdef wxUSE_BEGIN_THREAD
     _endthreadex(wxPtrToUInt(status));
 #else // !VC++
-    ::ExitThread((DWORD)status);
+    ::ExitThread(wxPtrToUInt(status));
 #endif // VC++/!VC++
 
     wxFAIL_MSG(wxT("Couldn't return from ExitThread()!"));