add default value for router path in the cert

roles/openshift_hosted/tasks/router/router.yml

@@ -23,8 +23,8 @@
       signer_key: "{{ openshift_master_config_dir }}/ca.key"
       signer_serial: "{{ openshift_master_config_dir }}/ca.serial.txt"
       hostnames:
-      - "{{ openshift_master_default_subdomain }}"
-      - "*.{{ openshift_master_default_subdomain }}"
+      - "{{ openshift_master_default_subdomain | default('router.default.svc.cluster.local') }}"
+      - "*.{{ openshift_master_default_subdomain | default('router.default.svc.cluster.local') }}"
       cert: "{{ ('/etc/origin/master/' ~ (item.certificate.certfile | basename)) if 'certfile' in item.certificate else ((openshift_master_config_dir) ~ '/openshift-router.crt') }}"
       key: "{{ ('/etc/origin/master/' ~ (item.certificate.keyfile | basename)) if 'keyfile' in item.certificate else ((openshift_master_config_dir) ~ '/openshift-router.key') }}"
     with_items: "{{ openshift_hosted_routers }}"