aibs / atk0110: add support for querying sensors via GGRP and GITM

Comparing to the Linux driver there is still one missing feature.
The Linux driver finds and enables "Embedded Controller" item in
the 0x11 group if it's not enabled yet.

I tested the new method, Torfinn Ingolfsen tested the old method
and helped to fix several bugs in the earlier versions of the patch.

Tested by: Torfinn Ingolfsen <torfinn.ingolfsen@getmail.no>
Reviewed by: rpaulo
MFC after: 3 weeks
Differential Revision: https://reviews.freebsd.org/D8227