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/generic/vscroll.cpp

@@ -155,7 +155,7 @@ wxVarScrollHelperBase::wxVarScrollHelperBase(wxWindow *win)
     m_unitFirst = 0;
 
     m_win =
-    m_targetWindow = (wxWindow *)NULL;
+    m_targetWindow = NULL;
 
     m_physicalScrolling = true;
     m_handler = NULL;