Remove wxMGL port.

The company behind MGL toolkit (SciTech) doesn't exist since several years and
this port is not used by anybody, so remove it to ease maintenance burden.


git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@70353 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

src/common/utilscmn.cpp

@@ -390,10 +390,6 @@ bool wxPlatform::Is(int platform)
     if (platform == wxOS_UNIX)
         return true;
 #endif
-#ifdef __WXMGL__
-    if (platform == wxPORT_MGL)
-        return true;
-#endif
 #ifdef __OS2__
     if (platform == wxOS_OS2)
         return true;