soc/intel/common/block: Add Intel common systemagent support

Add Intel common systemagent support for romstage and ramstage.
Include soc specific macros need to compile systemagent common code.

Change-Id: I969ff187e3d4199864cb2e9c9a13f4d04158e27c
Signed-off-by: V Sowmya <v.sowmya@intel.com>
Signed-off-by: Subrata Banik <subrata.banik@intel.com>
Reviewed-on: https://review.coreboot.org/19668
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>
6 files changed