add gec lock for use by gec_lpc interface

This is basically the same as the big lock, but with a different key.
New accessors were added for the gec-specific stuff.

BRANCH=link
BUG=none
TEST=Tested on link using simultaneous instances of mosys and ectool

Change-Id: Id45537712b9489b8c28eaac98569ab1a2d8138d6
Reviewed-on: https://gerrit.chromium.org/gerrit/30367
Commit-Ready: David Hendricks <dhendrix@chromium.org>
Reviewed-by: David Hendricks <dhendrix@chromium.org>
Tested-by: David Hendricks <dhendrix@chromium.org>
5 files changed