Use acpigen_write_processor_cnot to implement notifications to the CPU.
Automatically generate \PPKG in SSDT.
Change-Id: I79d2eed9b89b420554ce10d1fc0f151b1872afe2
Signed-off-by: Arthur Heymans <arthur@aheymans.xyz>
Reviewed-on: https://review.coreboot.org/c/29890
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Duncan Laurie <dlaurie@chromium.org>