ec: Add cros_ec support for ish variant

The Integrated Sensor Hub is a new EC type used on the Wilco platform.

BUG=b:130438917
TEST=mosys ish info on Sarien

Change-Id: Iae3b36e7b82c8f1322c69ba06eaa8215f1834d3c
Signed-off-by: Raul E Rangel <rrangel@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/1625452
Commit-Ready: ChromeOS CL Exonerator Bot <chromiumos-cl-exonerator@appspot.gserviceaccount.com>
Legacy-Commit-Queue: Commit Bot <commit-bot@chromium.org>
Reviewed-by: Jett Rink <jettrink@chromium.org>
9 files changed