mb/google/kahlee: Add SKU support

We want to report the board SKU via the SMBIOS tables. Add support for
this, obtaining the ID itself from the EC.

BUG=b:74175244
BRANCH=none
TEST=manually on grunt with another CL:
mosys platform sku
0

Change-Id: I9e08d64df3f89d3703de047dd9ec8e1717e6b212
Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-on: https://review.coreboot.org/25011
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
4 files changed