Tests: Don't attempt connection for Coho driver init
Tests: Don't attempt connection for Coho driver init

This test is unreliable because it tries to actually
connect to the network, and test for failure.

Rather than trying to actually make a connection,
just throw an error.

Change-Id: I896979516f4fc751a30998120f510c3a4e5f59f6
Closes-Bug: #1582370

bswartz/cinder,phenoxim/cinder,j-griffith/cinder,ge0rgi/cinder,cloudbase/cinder,openstack/cinder,cloudbase/cinder,Datera/cinder,openstack/cinder,mahak/cinder,Hybrid-Cloud/cinder,eharney/cinder,Datera/cinder,Nexenta/cinder,mahak/cinder,NetApp/cinder,Hybrid-Cloud/cinder,j-griffith/cinder,NetApp/cinder,Nexenta/cinder,bswartz/cinder,eharney/cinder,phenoxim/cinder