For completeness, this adds functions sys_window_fit_in_display
and sys_get_window_display_index.
Practically it has no effect as in ScummVM we don't support
multiscreen and the resolution is hardcoded.
Partially from upstream 1afc61df54681ffe2fddc0d30bb2221c38a0fa79 and
b17f58d90061c3b12c9e4c04183dc59b094d66cb