Remove violations plugin use.

Change-Id: If1d4795ae3182f19f4d58e0777880d8bc57feecd
Reviewed-on: https://review.openstack.org/33120
Reviewed-by: Jeremy Stanley <fungi@yuggoth.org>
Reviewed-by: Khai Do <zaro0508@gmail.com>
Approved: James E. Blair <corvus@inaugust.com>
Reviewed-by: James E. Blair <corvus@inaugust.com>
Tested-by: Jenkins