Remove unused clients from testcases

This is to remove unused clients from testcases to
keep code clean.

Change-Id: I7dd4f9194357de23ece44d25f70f86f498df8a07
diff --git a/tempest/api/compute/admin/test_live_migration.py b/tempest/api/compute/admin/test_live_migration.py
index 705e567..3f1bdce 100644
--- a/tempest/api/compute/admin/test_live_migration.py
+++ b/tempest/api/compute/admin/test_live_migration.py
@@ -48,7 +48,6 @@
     @classmethod
     def setup_clients(cls):
         super(LiveMigrationTest, cls).setup_clients()
-        cls.admin_hosts_client = cls.os_admin.hosts_client
         cls.admin_migration_client = cls.os_admin.migrations_client
 
     def _migrate_server_to(self, server_id, dest_host, volume_backed=False):
diff --git a/tempest/api/compute/admin/test_servers_negative.py b/tempest/api/compute/admin/test_servers_negative.py
index 9023759..3656770 100644
--- a/tempest/api/compute/admin/test_servers_negative.py
+++ b/tempest/api/compute/admin/test_servers_negative.py
@@ -32,7 +32,6 @@
     def setup_clients(cls):
         super(ServersAdminNegativeTestJSON, cls).setup_clients()
         cls.client = cls.os_admin.servers_client
-        cls.non_adm_client = cls.servers_client
         cls.quotas_client = cls.os_admin.quotas_client
 
     @classmethod
diff --git a/tempest/scenario/manager.py b/tempest/scenario/manager.py
index aecb374..7690d3b 100644
--- a/tempest/scenario/manager.py
+++ b/tempest/scenario/manager.py
@@ -240,7 +240,7 @@
 
     def create_volume_type(self, client=None, name=None, backend_name=None):
         if not client:
-            client = self.admin_volume_types_client
+            client = self.os_admin.volume_types_v2_client
         if not name:
             class_name = self.__class__.__name__
             name = data_utils.rand_name(class_name + '-volume-type')
diff --git a/tempest/scenario/test_volume_migrate_attached.py b/tempest/scenario/test_volume_migrate_attached.py
index 81b71b1..5667fbb 100644
--- a/tempest/scenario/test_volume_migrate_attached.py
+++ b/tempest/scenario/test_volume_migrate_attached.py
@@ -40,7 +40,6 @@
     @classmethod
     def setup_clients(cls):
         super(TestVolumeMigrateRetypeAttached, cls).setup_clients()
-        cls.admin_volume_types_client = cls.os_admin.volume_types_v2_client
         cls.admin_volumes_client = cls.os_admin.volumes_v2_client
 
     @classmethod