nsm: add authentication tlv for nsm add sad_process_auth() and sad_append_auth_tlv() to the nsm_recv() and nsm_request() functions. In addition, add spp to the nsm structure and add sad_create() & sad_destroy() to functions. Signed-off-by: Clay Kaiser <Clay.Kaiser@ibm.com> Reviewed-by: Erez Geva <ErezGeva2@gmail.com> Reviewed-by: Miroslav Lichvar <mlichvar@redhat.com>