Add 8.0 machine types for arm/i440fx/m68k/q35/s390x/spapr.

Reviewed-by: Cédric Le Goater <clg@kaod.org> [ppc]
Reviewed-by: Thomas Huth <thuth@redhat.com> [s390x]
Reviewed-by: Greg Kurz <groug@kaod.org> [ppc]
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
Message-Id: <20221212152145.124317-2-cohuck@redhat.com>
Reviewed-by: Michael S. Tsirkin <mst@redhat.com>
Signed-off-by: Michael S. Tsirkin <mst@redhat.com>
Reviewed-by: Cédric Le Goater <clg@kaod.org>