Add 8.1 machine types for arm/i440fx/m68k/q35/s390x/spapr.

Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20230314173009.152667-1-cohuck@redhat.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>
Reviewed-by: Thomas Huth <thuth@redhat.com>
Acked-by: Gavin Shan <gshan@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>