Insure the admin_conn is disconnected on stop

If we stop or restart the server insure admin_conn gets reset or other
parts may fail to properly connect/authenticate

Signed-off-by: Simo Sorce <simo@redhat.com>
Reviewed-By: Jan Cholasta <jcholast@redhat.com>

ipaserver/install/dsinstance.py

@@ -530,7 +530,14 @@ class DsInstance(service.Service):
             # Does not apply with newer DS releases
             pass
 
+    def stop(self, *args, **kwargs):
+        if self.admin_conn:
+            self.ldap_disconnect()
+        super(DsInstance, self).stop(*args, **kwargs)
+
     def restart(self, instance=''):
+        if self.admin_conn:
+            self.ldap_disconnect()
         try:
             super(DsInstance, self).restart(instance)
             if not is_ds_running(instance):