google/gru: Add code to support I2C TPM for Kevin

Coming Kevin revisions will switch back to an I2C TPM. This patch adds
the required configuration options and code to support that. Since the
TPM type can currently only be changed at compile time, we can no longer
support older Kevins with the same image. In order to build for Kevin
revisions < 5, you have to explicitly override the CONFIG_GRU_HAS_TPM2.

BRANCH=None
BUG=chrome-os-partner:55523
TEST=Compiled both Kevin and Gru, confirmed that bootblock and verstage
binary had the appropriate code differences.

Change-Id: I81a15c9fb037a7ca2d69818e46cbb4f9a5ae1989
Signed-off-by: Julius Werner <jwerner@chromium.org>
Reviewed-on: https://chromium-review.googlesource.com/364222
Reviewed-by: Douglas Anderson <dianders@chromium.org>
(cherry picked from commit 3245bff937154f0f9f39894de9c98a75631d59d9)
Reviewed-on: https://chromium-review.googlesource.com/365435
Tested-by: Douglas Anderson <dianders@chromium.org>
3 files changed