[$] Some near-term arm64 hardening patches

The arm64 architecture is found at the core of many, if not most, mobiledevices; that means that arm64 devices are destined to be the target ofattackers worldwide. That has led to a high level of interest intechnologies that can harden these systems. There are currently severalsuch technologies, based in both hardware and software, that are beingreadied for the arm64 kernel; read on for a survey on what iscoming.