This commit has changes for below 3 items.
1) It adds _get_iscsi_conn_props to process connection_info data for
iSCSI properties.
2) It removes the target_name when creating scsi mapping because that's
now being handled correctly at the platform level.
3) It adds more testing around 'CHAP' auth_method.
Change-Id: Ib6deef7b15bdb73a23f5edb5ec3fb6cbc9fe4e93