soc/intel/common: Add IGD OpRegion support

Add helper function that fills OpRegion structure based on
VBT file content and some reasonable defaults.

Change-Id: I9aa8862878cc016a9a684c844ceab390734f3e84
Signed-off-by: Andrey Petrov <andrey.petrov@intel.com>
Reviewed-on: https://review.coreboot.org/14806
Tested-by: build bot (Jenkins)
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
5 files changed