Merge pull request #1915 from Diapolo/Qt5_compat_leftover

change Q_WS_MAC -> Q_OS_MAC (Qt5 compatibility)

src/qt/optionsdialog.cpp

@@ -139,7 +139,7 @@ void OptionsDialog::setMapper()
     mapper->addMapping(ui->socksVersion, OptionsModel::ProxySocksVersion);
 
     /* Window */
-#ifndef Q_WS_MAC
+#ifndef Q_OS_MAC
     mapper->addMapping(ui->minimizeToTray, OptionsModel::MinimizeToTray);
     mapper->addMapping(ui->minimizeOnClose, OptionsModel::MinimizeOnClose);
 #endif