Remove resource_setup() from test_live_migration

The resource_setup() becomes meaningless, so let's remove it.

Change-Id: Id6de9b89aca0384e1e73a22ac39ff440cc15c097
diff --git a/tempest/api/compute/admin/test_live_migration.py b/tempest/api/compute/admin/test_live_migration.py
index 12c471e..f186a7d 100644
--- a/tempest/api/compute/admin/test_live_migration.py
+++ b/tempest/api/compute/admin/test_live_migration.py
@@ -34,10 +34,6 @@
         cls.admin_servers_client = cls.os_adm.servers_client
         cls.admin_migration_client = cls.os_adm.migrations_client
 
-    @classmethod
-    def resource_setup(cls):
-        super(LiveBlockMigrationTestJSON, cls).resource_setup()
-
     def _get_compute_hostnames(self):
         body = self.admin_hosts_client.list_hosts()['hosts']
         return [