common_functions.sh statically uses virtio, and when /dev/disk/by-id fails it looks for the exsistance of /dev/vda /dev/vdb

If you are using a different driver such as virtio-scsi these devices are mounted as /dev/sda /dev/sdb

This is usually done when Ceph is the backend for Openstack which is a pretty common use case, so in common_functions.sh could we add a check for /dev/sda /dev/sdb?

This would also help support future bare metal ironic deployments of Openshift on Openstack