Merge remote-tracking branch 'vfio-ap' into next

The Secure Execution AP support makes it possible for SE VMs to
securely use APQNs without a third party being able to snoop IO. VMs
first bind to an APQN to securely attach it and granting protected key
crypto function access. Afterwards they can associate the APQN which
grants them clear key crypto function access. Once bound the APQNs are
not accessible to the host until a reset is performed.

The vfio-ap patches being merged here provide the base hypervisor
Secure Execution / Protected Virtualization AP support. This includes
proper handling of APQNs that are securely attached to a SE/PV guest
especially regarding resets.