rem: struct scsi_unit *scsi_units, int n_scsi_units)
add: struct scsi_unit *units, int n_units)
context: add_linux_cd_recorder (GList *cdroms,		       struct cdrom_unit *cdrom_s,		       struct scsi_unit *scsi_units,		       int n_scsi_units){	int bus, id, lun;	CDDrive *cdrom;	if (!get_cd_scsi_id (cdrom_s->device, &bus, &id, &lun)) {		return cdroms;	}	cdrom = g_new0 (CDDrive, 1);	cdrom->device = g_strdup_printf ("/dev/%s", cdrom_s->device);	cdrom->cdrecord_id = g_strdup_printf ("%d,%d,%d",					      bus, id, lun);	cdrom->display_name = get_scsi_cd_name (bus, id, lun, cdrom_s->device, scsi_units, n_scsi_units);	cdrom->max_speed_write = get_device_max_speed (cdrom->cdrecord_id);	cdrom->max_speed_read = cdrom_s->speed; 	if (cdrom_s->can_write_dvdr	    || cdrom_s->can_write_dvdram) {		cdrom->type = CDDRIVE_TYPE_DVD_RECORDER;	} else {		cdrom->type = CDDRIVE_TYPE_CD_RECORDER;	}		return g_list_append (cdroms, cdrom);}