create_l2
l2 = create_l2(crq->ch, crq->protocol, 0, 0, 0);
extern struct layer2 *create_l2(struct mISDNchannel *, u_int,
l2 = create_l2(crq->ch, crq->protocol, opt,
l2 = create_l2(mgr->up, ISDN_P_LAPD_NT, opt, tei, sapi);