Nothing in eRoT state survives a power cycle

[chrysh]

Retry budgets, isolation state, and Locked itself are RAM-only — a power cycle is a lockdown escape. LatchLockdown delegates durability to a shell that doesn't exist yet. Ask what the persistence story is; it interacts with the pending-update record (#383), so they may share a mechanism.

cc @FerralCoder @rusty1968

[FerralCoder]

I would like to consult our partners on how this is typically handled today.

• Does eRoT/PRoT save any persistent data on power cycle?
• Under what condition would PRoT be power cycled? I am assuming this is rare (i.e. not cycled along with the rest of the system such as when updating/recovery of downstream components like BMC or CPU etc.