libpayload: Add gru config

This adds a gru libpayload config, that should fit all gru-based
devices such as kevin.

As gru-based devices are CrOS devices, select the associated config
to enable CrOS-specific features.

Change-Id: I6e79b763fc497c126612b8786a669a33b57ea29f
Signed-off-by: Paul Kocialkowski <contact@paulk.fr>
Reviewed-on: https://review.coreboot.org/19137
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Julius Werner <jwerner@chromium.org>
1 file changed