hid: Import multitouch driver (hmt)

[wulf]

Summary

This imports hmt(4) driver which is conversion of existing wmt(4) to the HID subsystem.

Unlike wmt(4) which is monolitic, hmt(4) is splitted on two parts hmt(4) itself and hconf(4) (configuration driver) as according MS specs it uses several top level collections resulting in creation of several hidbus children.

This revision is subset of https://reviews.freebsd.org/D27777

[• hselasky]

@wulf : It will take some time to review. I'm currently flooded with work.

[wulf]

In D27990#625272, @hselasky wrote:

@wulf : It will take some time to review. I'm currently flooded with work.

No problems. All KPI changes are reviewed already, so no Jan 8 deadline to review remaining.