KVM/arm64 fixes for 7.2, take #2
- Move locking for kvm_io_bus_get_dev() into the caller, ensuring
race-free checks that the returned object is of the correct type
- Fix initialisation of the page-table walk level when relaxing
permissions
- Correctly update the XN attribute when relaxing permissions
- Fix the sign extension of loads from emulated MMIO regions
- Assorted collection of fixes for pKVM's FFA proxy, together with a
couple of FFA driver adjustments
15f8ba7806