Remove openstack.common.exception usage
Remove openstack.common.exception usage

This file is deprecated, stop using it.

Change-Id: I5d79b8c0134bb5f4021487542d4d0a964281b8bf
Fixes-Bug: #1208734

stackforge/networking-mlnx,openstack/networking-mlnx,openstack/networking-mlnx,stackforge/networking-mlnx,moshele/networking-mlnx-master,moshele/networking-mlnx