Enable HostsAdminTestXML

Although there is hosts_client class for XML, HostsAdminTestXML is
disabled. This patch enables HostsAdminTestXML.

Change-Id: Ib136661107a94f3e2c1607dad644dce0a3b42502
Closes-Bug: #1261968
diff --git a/tempest/clients.py b/tempest/clients.py
index ac79ce0..fe5ed74 100644
--- a/tempest/clients.py
+++ b/tempest/clients.py
@@ -87,6 +87,7 @@
 from tempest.services.compute.xml.flavors_client import FlavorsClientXML
 from tempest.services.compute.xml.floating_ips_client import \
     FloatingIPsClientXML
+from tempest.services.compute.xml.hosts_client import HostsClientXML
 from tempest.services.compute.xml.hypervisor_client import HypervisorClientXML
 from tempest.services.compute.xml.images_client import ImagesClientXML
 from tempest.services.compute.xml.instance_usage_audit_log_client import \
@@ -242,6 +243,7 @@
                 *client_args)
             self.tenant_usages_client = TenantUsagesClientXML(*client_args)
             self.policy_client = PolicyClientXML(*client_args)
+            self.hosts_client = HostsClientXML(*client_args)
             self.hypervisor_v3_client = HypervisorV3ClientXML(*client_args)
             self.hypervisor_client = HypervisorClientXML(*client_args)
             self.token_v3_client = V3TokenClientXML(*client_args)
@@ -293,6 +295,7 @@
                 *client_args)
             self.tenant_usages_client = TenantUsagesClientJSON(*client_args)
             self.policy_client = PolicyClientJSON(*client_args)
+            self.hosts_client = HostsClientJSON(*client_args)
             self.hypervisor_v3_client = HypervisorV3ClientJSON(*client_args)
             self.hypervisor_client = HypervisorClientJSON(*client_args)
             self.token_v3_client = V3TokenClientJSON(*client_args)
@@ -310,7 +313,6 @@
             raise exceptions.InvalidConfiguration(msg)
 
         # common clients
-        self.hosts_client = HostsClientJSON(*client_args)
         self.account_client = AccountClient(*client_args)
         if self.config.service_available.glance:
             self.image_client = ImageClientJSON(*client_args)