asus/p2b-ls: Add ACPI tables

Add ACPI tables support that will be needed for soft-off and S3 resume in the future.
Boot tested for soft-off.

Change-Id: I28b559406bd53efc555dcbb8282dfe2bd6d1af87
Signed-off-by: Keith Hui <buurin@gmail.com>
Reviewed-on: https://review.coreboot.org/21672
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Stefan Reinauer <stefan.reinauer@coreboot.org>
3 files changed