Implement display="on" and ramfb="on" for vfio PCI host devices in qemu.
This enables passthrough PCI devices for display just like we did for
mdevs.
Resolves: https://issues.redhat.com/browse/RHEL-28808
Signed-off-by: Jonathon Jongsma <jjongsma@redhat.com>
Reviewed-by: Michal Privoznik <mprivozn@redhat.com>
