== DETAILS
I've created the concept of a hid_driver_instance_t which is basically
a central place to store the hid pad driver, hid subsystem driver,
the pad list, and the instance data for the above in a central location.
The HID pad device drivers can use it to perform HID operations in a
generic manner.
This is more-or-less a pause point so I can catch up with upstream.
== TESTING
Haven't tested this yet. Compiles without warnings though!
