security/blessingstore: Remove old serialization format that should not be used anywhere by now.
security/blessingstore: Remove old serialization format that should
not be used anywhere by now.

Change-Id: I39742e1bae4533b7035237302a3cf6f58dda0783

vanadium/go.ref,vanadium/go.ref,vanadium/go.ref,vanadium/go.ref,vanadium/go.ref,vanadium/go.ref