txt: Xen per-domain S3 integrity config

txt: Xen per-domain S3 integrity config

This patch adds a per-domain flag to specify whether a domain will be
S3 integrity protected when Xen is launched using tboot/TXT.

The tools now support an integer domain configuration parameter called
's3_integrity', which defaults to 1, to enable S3 integrity protection.

The struct arch_domain structure has been extended to have an
's3_integrity' field that represents this setting.

Signed-off-by: Shane Wang <shane.wang@intel.com>
Signed-off-by: Joseph Cihula <joseph.cihula@intel.com>