Remove unused LOG variable in scenario tests

In some scenario tests, there are unused LOG variables.
This commit removes them and their 'import log' too.

Change-Id: I318fa5783ddb55796082963052ab73135a697988
diff --git a/tempest/scenario/orchestration/test_autoscaling.py b/tempest/scenario/orchestration/test_autoscaling.py
index 17870a1..78025ee 100644
--- a/tempest/scenario/orchestration/test_autoscaling.py
+++ b/tempest/scenario/orchestration/test_autoscaling.py
@@ -12,16 +12,12 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-from tempest.openstack.common import log as logging
 from tempest.scenario import manager
 from tempest.test import attr
 from tempest.test import call_until_true
 import time
 
 
-LOG = logging.getLogger(__name__)
-
-
 class AutoScalingTest(manager.OrchestrationScenarioTest):
 
     def setUp(self):
diff --git a/tempest/scenario/test_snapshot_pattern.py b/tempest/scenario/test_snapshot_pattern.py
index 95d2862..003c264 100644
--- a/tempest/scenario/test_snapshot_pattern.py
+++ b/tempest/scenario/test_snapshot_pattern.py
@@ -15,13 +15,9 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-from tempest.openstack.common import log as logging
 from tempest.scenario import manager
 
 
-LOG = logging.getLogger(__name__)
-
-
 class TestSnapshotPattern(manager.OfficialClientTest):
     """
     This test is for snapshotting an instance and booting with it.
diff --git a/tempest/scenario/test_volume_snapshot_pattern.py b/tempest/scenario/test_volume_snapshot_pattern.py
index 8fa177e..d873d30 100644
--- a/tempest/scenario/test_volume_snapshot_pattern.py
+++ b/tempest/scenario/test_volume_snapshot_pattern.py
@@ -12,13 +12,9 @@
 #    License for the specific language governing permissions and limitations
 #    under the License.
 
-from tempest.openstack.common import log as logging
-
 from tempest.common.utils.data_utils import rand_name
 from tempest.scenario import manager
 
-LOG = logging.getLogger(__name__)
-
 
 class TestVolumeSnapshotPattern(manager.OfficialClientTest):