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

src/x11/region.cpp

@@ -337,7 +337,7 @@ wxRegionContain wxRegion::DoContainsRect(const wxRect& r) const
 WXRegion *wxRegion::GetX11Region() const
 {
     if (!m_refData)
-        return (WXRegion*) NULL;
+        return NULL;
 
     return (WXRegion*) M_REGIONDATA->m_region;
 }