One pager on SVSM_REBOOT_EXECUTE

In our 15-October-2025 Coconut SVSM meeting, I agreed to write up a one-pager describing the initial implementation of the SVSM Reboot Protocol.

I’ve attached Tom’s original 2-pager full specification for the protocol with modifications. The substantive change is to replace "Rebooting the guest will restore the guest state to match that of a newly booted guest.” With "Rebooting the guest invalidates memory pages that were validated by the guest and resets the CPU register state to their initial state. No other system state is modified.”

Richard