hw/s390x: Remove the "adapter_routes_max_batch" property from the flic

hw/s390x: Remove the "adapter_routes_max_batch" property from the flic

Now that the s390-ccw-virtio-2.8 machine has been removed, we don't
need the "adapter_routes_max_batch" property anymore and can remove it.

Reviewed-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Tested-by: Philippe Mathieu-Daudé <philmd@linaro.org>
Reviewed-by: Cornelia Huck <cohuck@redhat.com>
Acked-by: Christian Borntraeger <borntraeger@linux.ibm.com>
Message-ID: <20250103144232.520383-11-thuth@redhat.com>
Signed-off-by: Thomas Huth <thuth@redhat.com>