soc/intel/cannonlake: Add PCH ID support in bootblock/report_platform.c

This patch ensures that all required information for pch/mch/igd
deviceid and revision are available in single stage and makes
use of local references.

TEST=Build and boot cannonlake_rvp to get PCH information as below
PCH: device id xxxx (rev xx) is Cannonlake-Y Premium

Change-Id: I420e94043145e8a5adcf8bb51239657891915d84
Signed-off-by: Subrata Banik <subrata.banik@intel.com>
Reviewed-on: https://review.coreboot.org/22767
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Furquan Shaikh <furquan@google.com>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
2 files changed