Don't fall when just loading barbicanv1 modules

this avoids loading warnings on salt-master that may not have
os-client-config installed, as salt tries to load them irrespective of
__virtual__() result.

Change-Id: I819d46d5dbd0339e7a5e53609d43e34da992db60
Related-Issue: https://mirantis.jira.com/browse/PROD-26920
(cherry picked from commit 7cd57571cd993afea59b5742d5d8cce22612a217)
1 file changed