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/common/fs_inet.cpp

@@ -129,7 +129,7 @@ wxFSFile* wxInternetFSHandler::OpenFile(wxFileSystem& WXUNUSED(fs),
         }
     }
 
-    return (wxFSFile*) NULL; // incorrect URL
+    return NULL; // incorrect URL
 #endif
 }