Remove power state constants that have ended up duplicated following a bad

merge. They were moved from nova.compute.node.Instance into
nova.compute.power_state at the same time that Instance was moved into
nova.compute.service. We've ended up with these constants in both places.

Remove the ones from service, in favour of the ones in power_state.

nova/tests/cloud_unittest.py

@@ -28,6 +28,7 @@ from nova import flags
 from nova import rpc
 from nova import test
 from nova.auth import manager
+from nova.compute import power_state
 from nova.compute import service
 from nova.endpoint import api
 from nova.endpoint import cloud
@@ -95,7 +96,7 @@ class CloudTestCase(test.BaseTestCase):
             rv = yield defer.succeed(time.sleep(1))
             info = self.cloud._get_instance(instance['instance_id'])
             logging.debug(info['state'])
-            if info['state'] == node.Instance.RUNNING:
+            if info['state'] == power_state.RUNNING:
                 break
         self.assert_(rv)