Remove unused logging import and LOG global var

In some modules the global LOG is not used any more. And the import
of logging is not used. This patch removes the unused logging import
and LOG vars.

Change-Id: I794ee719d76f04e70154cf67f726152fbb1ba15a

watcher/decision_engine/planner/loading/default.py

@@ -17,12 +17,8 @@
 
 from __future__ import unicode_literals
 
-from oslo_log import log
-
 from watcher.common.loader.default import DefaultLoader
 
-LOG = log.getLogger(__name__)
-
 
 class DefaultPlannerLoader(DefaultLoader):
     def __init__(self):