don't use annoying and unneeded in C++ casts of NULL to "T *" in all other files neither

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@58227 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/univ/menuitem.h

@@ -20,12 +20,12 @@ class WXDLLIMPEXP_CORE wxMenuItem : public wxMenuItemBase
 {
 public:
     // ctor & dtor
-    wxMenuItem(wxMenu *parentMenu = (wxMenu *)NULL,
+    wxMenuItem(wxMenu *parentMenu = NULL,
                int id = wxID_SEPARATOR,
                const wxString& name = wxEmptyString,
                const wxString& help = wxEmptyString,
                wxItemKind kind = wxITEM_NORMAL,
-               wxMenu *subMenu = (wxMenu *)NULL);
+               wxMenu *subMenu = NULL);
     virtual ~wxMenuItem();
 
     // override base class virtuals to update the item appearance on screen