Add ACPI Methods to enable and disable power limiting with PL1. This can be used in ACPI Thermal Zone or in EC ACPI _QXX events. This commit adds new unused methods and is fully tested with the subsequent commit that makes use of these methods. Change-Id: I9d8d23bfe9cf7c756ff8ab0412e5a010826b12db Signed-off-by: Duncan Laurie <dlaurie@chromium.org> Reviewed-on: https://gerrit.chromium.org/gerrit/60546 Reviewed-on: http://review.coreboot.org/4334 Reviewed-by: Alexandru Gagniuc <mr.nuke.me@gmail.com> Tested-by: build bot (Jenkins)