google/oak: Add initial support for Rowan

Update GPIO controls and mainboard configurations for Rowan.

BUG=chrome-os-partner:62672
BRANCH=none
TEST=emerge-rowan coreboot

Change-Id: I18ebc3ccf4c7d051839d7c50e9b0682ef8f09830
Signed-off-by: Yidi Lin <yidi.lin@mediatek.com>
Reviewed-on: https://chromium-review.googlesource.com/430557
Reviewed-by: Julius Werner <jwerner@chromium.org>
5 files changed