Hopefully finish removing the old wxCocoa port.

Get rid of the rest of __WXCOCOA__ tests in the sources.

Drop configure option for using it.

Also remove the documentation for this port.

This should have also been part of r76735.

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@76815 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/mdi.h

@@ -348,8 +348,7 @@ public:
     // wxUniv always uses the generic MDI implementation and so do the ports
     // without native version (although wxCocoa seems to have one -- but it's
     // probably not functional?)
-    #if defined(__WXCOCOA__) || \
-        defined(__WXMOTIF__) || \
+    #if defined(__WXMOTIF__) || \
         defined(__WXUNIVERSAL__)
         #define wxUSE_GENERIC_MDI_AS_NATIVE   1
     #else