wxSocketImpl::Shutdown() doesn't need to be virtual, its implementation can the same in Unix and Win32 versions (events are already disabled by Close() so there is no need to do it again explicitly under Unix)

git-svn-id: https://svn.wxwidgets.org/svn/wx/wxWidgets/trunk@57611 c3d73ce0-8a6f-49c7-b76d-6d57e0e08775

include/wx/private/socket.h

@@ -250,7 +250,11 @@ public:
     // it was indeed created
     void Close();
 
-    virtual void Shutdown();
+    // shuts down the writing end of the socket and closes it, this is a more
+    // graceful way to close
+    //
+    // does nothing if the socket wasn't created
+    void Shutdown();
 
 
     // IO operations