Add acpigen_write_opregion that generates ACPI AML code for OperationRegion, region name, region space, region length & region size are inputs. Add acpigen_write_field that generates ACPI AML code for Field. Operation region name & field list are inputs. Change-Id: I578834217d39aa3b0d409eb8ba4b5f7a31969fa8 Signed-off-by: Naresh G Solanki <naresh.solanki@intel.com> Reviewed-on: https://review.coreboot.org/17113 Reviewed-by: Furquan Shaikh <furquan@google.com> Tested-by: build bot (Jenkins)