soc/intel/common/block: Manage power state variable from common PMC block

This patch helps managing power state variables from within the
library. Adds migrate_power_state which migrates the chipset
power state variable, reads global power variable and adds it
in cbmem for future use. This also adds get_soc_power_state_values
function which returns the power state variable from cbmem or
global power state variable if cbmem is not populated yet.

Change-Id: If65341c1492e3a35a1a927100e0d893f923b9e68
Signed-off-by: Shaunak Saha <shaunak.saha@intel.com>
Reviewed-on: https://review.coreboot.org/21851
Reviewed-by: Furquan Shaikh <furquan@google.com>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
2 files changed