Utility function implementation of _get_friendly_zone_name.
Get friendly zone name is used to form the zone name based on the details provided by the caller
:param zoning_policy - determines the zoning policy is either initiator-target or initiator :param initiator - initiator WWN :param target - target WWN :param host_name - Host name returned from Volume Driver :param storage_system - Storage name returned from Volume Driver :param zone_name_prefix - user defined zone prefix configured in cinder.conf :param supported_chars - Supported character set of FC switch vendor. Example: ‘abc123_-$’. These are defined in the FC zone drivers.