Convert all boards to use the servod 'power_state' control.

All boards now provide the standard board-independent interface for
power off, power on, recovery mode, and cold reset operations.

BUG=chromium:342875,chromium:326738
TEST=Pending

Change-Id: Ic68017a598df3745347ceff90cc8d8faf8e344fe
Reviewed-on: https://chromium-review.googlesource.com/202720
Tested-by: Richard Barnette <jrbarnette@chromium.org>
Reviewed-by: Kris Rambish <krisr@chromium.org>
Reviewed-by: Dan Shi <dshi@chromium.org>
Commit-Queue: Richard Barnette <jrbarnette@chromium.org>
7 files changed