google/reef: Add coral

A new variant copied from reef.
Allow override of the SKU.

Change-Id: Ibe160e75aa23623812f0fb9121d1d8226afc00d8
Signed-off-by: Patrick Georgi <pgeorgi@google.com>
Reviewed-on: https://review.coreboot.org/20020
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
9 files changed