s390x/css: attach css bridge

Logically, the css bridge should be attached to the machine.

Reviewed-by: Christian Borntraeger <borntraeger@de.ibm.com>
Reviewed-by: David Hildenbrand <david@redhat.com>
Tested-by: Bjoern Walk <bwalk@linux.vnet.ibm.com>
Signed-off-by: Cornelia Huck <cohuck@redhat.com>
1 file changed