Warning fixes for VC5 (Igor Korot)

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@37526 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/common/socket.cpp

@@ -159,7 +159,7 @@ void wxSocketBase::Shutdown()
 {
     // we should be initialized
     wxASSERT_MSG( m_countInit, _T("extra call to Shutdown()") );
-    if ( !--m_countInit )
+    if ( --m_countInit == 0 )
     {
         GSocket_Cleanup();
     }