Correct the description for Ironic

refer to https://github.com/openstack/ironic/blob/master/devstack/lib/ironic#L1387

Change-Id: I49d0a3cb5084813d7fb968435d013250af9b9476

ansible/roles/ironic/tasks/register.yml

@@ -5,7 +5,7 @@
     module_args:
       service_name: "ironic"
       service_type: "baremetal"
-      description: "Ironic bare metal provisioning service"
+      description: "Ironic baremetal provisioning service"
       endpoint_region: "{{ openstack_region_name }}"
       url: "{{ item.url }}"
       interface: "{{ item.interface }}"