VC6 compilation fix for native wxProgressDialog implementation.

Don't use return with a void value, VC6 doesn't support this and it's
unnecessary here anyhow.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@65354 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/msw/progdlg.cpp

@@ -561,7 +561,7 @@ void wxProgressDialog::SetTitle(const wxString& title)
     }
 #endif // wxHAS_MSW_TASKDIALOG
 
-    return wxGenericProgressDialog::SetTitle(title);
+    wxGenericProgressDialog::SetTitle(title);
 }
 
 wxString wxProgressDialog::GetTitle() const