Clean up unstack.sh and clean.sh errors

No need for bogus messages:
* Keystone site error
* Extraneous tgt and LVM errors

Change-Id: Icd7a00a35d025dae63ce4a1c9ecb8c82e173dfb1
Merge branch 'test-ca' into dt-test
Merge branch 'usb-prereq' into dt-test
Merge branch 'conf-tempest' into dt-test
Merge branch 'test-service-functions' into dt-test
Merge branch 'exercise-refresh' into dt-test