arm: Add Hypervisor.framework build target

arm: Add Hypervisor.framework build target

Now that we have all logic in place that we need to handle Hypervisor.framework
on Apple Silicon systems, let's add CONFIG_HVF for aarch64 as well so that we
can build it.

Signed-off-by: Alexander Graf <agraf@csgraf.de>
Reviewed-by: Roman Bolshakov <r.bolshakov@yadro.com>
Tested-by: Roman Bolshakov <r.bolshakov@yadro.com> (x86 only)
Reviewed-by: Peter Maydell <peter.maydell@linaro.org>
Reviewed-by: Sergio Lopez <slp@redhat.com>
Message-id: 20210916155404.86958-9-agraf@csgraf.de
Signed-off-by: Peter Maydell <peter.maydell@linaro.org>