libpayload: Update ARM CrOS devices configuration

This updates the configuration for ARM CrOS devices (nyans and veyrons)
by using the CHROMEOS Kconfig option, thus reducing the number of
options to select. It also brings proper serial console support.

Change-Id: Iffc84c44a1d339c5bb575fbaffc40bc2d56bb6cf
Signed-off-by: Paul Kocialkowski <contact@paulk.fr>
Reviewed-on: https://review.coreboot.org/17928
Tested-by: build bot (Jenkins)
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Julius Werner <jwerner@chromium.org>
2 files changed