Lock down SMM space on i82810 MCH and later chips in case BIOS didn't it already for us.
Lock down SMM space on i82810 MCH and later chips in case BIOS
didn't it already for us.

Reported by loic.duflot@sgdn.pm.gouv.fr via deraadt@.

ok deraadt@ weingart@

orumin/openbsd-efivars,orumin/openbsd-efivars,orumin/openbsd-efivars,orumin/openbsd-efivars