usnic_transport_sock_get_addr
err = usnic_transport_sock_get_addr(sock, &proto, &addr, &port_num);
err = usnic_transport_sock_get_addr(qp_flow->udp.sock,
err = usnic_transport_sock_get_addr(sock, &proto, &addr, &port);
int usnic_transport_sock_get_addr(struct socket *sock, int *proto,