KVM: arm64: Handle FFA_MEM_RECLAIM calls from the host

Intecept FFA_MEM_RECLAIM calls from the host and transition the host
stage-2 page-table entries from the SHARED_OWNED state back to the OWNED
state once EL3 has confirmed that the secure mapping has been reclaimed.

Signed-off-by: Will Deacon <will@kernel.org>
Link: https://lore.kernel.org/r/20230523101828.7328-8-will@kernel.org


Signed-off-by: Oliver Upton <oliver.upton@linux.dev>