ipaservice: Handle smb services as other services.

In current implementation, when using `smb: yes`, only a small subset
of the attributes can be used in the playbook. This happened due the
use of `service_add_smb`, which adds a new service and does not modify
an existing one, and not coping with attributes not supported by this
IPA API call.

The implementation was modified so that a service with `smb: true` is
treated like any other service, which, in effect, simplified and fixed
service search, and allowed for the use of the same attributes as with
any service. Although simplified, when using `smb: true` an extra
query is done against the LDAP server, as a second `service_show` is
performed.

Tests have been updated to reflect the new imprlementation.

tests/service/test_service.yml

@@ -469,6 +469,7 @@
         ipaservice:
           ipaadmin_password: SomeADMINpassword
           name: "{{ host1_fqdn }}"
+          pac_type: NONE
           smb: yes
           netbiosname: SAMBASVC
         register: result
@@ -478,11 +479,42 @@
         ipaservice:
           ipaadmin_password: SomeADMINpassword
           name: "{{ host1_fqdn }}"
+          pac_type: NONE
           smb: yes
           netbiosname: SAMBASVC
         register: result
         failed_when: result.changed or result.failed
 
+      - name: Modify SMB service.
+        ipaservice:
+          ipaadmin_password: SomeADMINpassword
+          name: "{{ host1_fqdn }}"
+          smb: yes
+          netbiosname: SAMBASVC
+          allow_retrieve_keytab_user:
+            - user01
+            - user02
+          allow_retrieve_keytab_group:
+            - group01
+            - group02
+        register: result
+        failed_when: not result.changed or result.failed
+
+      - name: Modify SMB service, again.
+        ipaservice:
+          ipaadmin_password: SomeADMINpassword
+          name: "{{ host1_fqdn }}"
+          smb: yes
+          netbiosname: SAMBASVC
+          allow_retrieve_keytab_user:
+            - user01
+            - user02
+          allow_retrieve_keytab_group:
+            - group01
+            - group02
+        register: result
+        failed_when: result.changed or result.failed
+
       - name: Ensure SMB service is absent.
         ipaservice:
           ipaadmin_password: SomeADMINpassword