devstack: add trustee conf regardless of keystone
devstack: add trustee conf regardless of keystone

In a multi node environment, nodes running any karbor services (api,
protection, operationengine) may not have keystone installed on them,
but are configured to speak with keystone configured on another node.
Set the trustee regardless of whether keystone is set on this node or
not.

Change-Id: Iad64680f39c12e02bad88da62693bbdba3e89cd5

openstack/smaug,openstack/smaug