window port interface change - add mbehavior flags to start_menu()

Provide a way to communicate additional behaviors and/or appearances
desired from NetHack window port menus.

This is foundation work for changes to follow at a future date.

win/share/safeproc.c

@@ -226,8 +226,9 @@ boolean complain;
 }
 
 void
-safe_start_menu(window)
+safe_start_menu(window, mbehavior)
 winid window;
+unsigned long mbehavior;
 {
     return;
 }