This enables use of software or hardware transports viz. be2iscsi,
bnx2i, cxgb3i, cxgb4i, qla4xx, iser and ocs. The default transport
(tcp) happens to be called "default".
Use of non-default transports changes the disk path to the following format:
/dev/disk/by-path/pci-<pci_id>-ip-<portal>-iscsi-<iqn>-lun-<lun_id>