Some initial support for IOHIDSystem. This gives us some pointer moves in X11
(not really related the the actual mouse movement, but this will come).
The darwin_iohidsystem_thread reads events from wscons, translates them
into IOHIDSystem events and wakes up the userland client with a notification.
To do this, I had to improve the void implementation of
io_connect_set_notification_port() to actually register something (I assumed
a single notification port, which makes some sense since only one process
seems to be able to open the driver)
Missing bits:
- we do not take event masks given by the process into account.
- the notification message has not been checked against Darwin
- events are badly translated
f816300903