A change was made to tempest.conf for volume multibackend. Previously,
tempest used the following, with a limit of 2 backends:
backend1_name = BACKEND1
backend2_name = BACKEND2
That was changed to accomodate >2 backends. tempest.conf now uses a comma
separated list:
backend_names=BACKEND1,BACKEND2,BACKEND3
devstack/lib/cinder uses a comma separated list with "type:backend_name":
enabled_backends = lvm:BACKEND1,ceph:BACKEND2
This is in order to use scripts in devstack/lib/cinder_backends to setup
devstack basked on "type".
This patch allows parsing of the CINDER_ENABLED_BACKENDS to pass the proper
backend_name to tempest.
Change-Id: I76973c3fad4998a0f9e534fc9f6a271c1923f7b3
3ac1ea85b1