sctp: Correctly track if AUTH has been bundled.

We currently track if AUTH has been bundled using the 'auth'
pointer to the chunk.  However, AUTH is disallowed after DATA
is already in the packet, so we need to instead use the
'has_auth' field.
Signed-off-by: NVlad Yasevich <vladislav.yasevich@hp.com>

net/sctp/output.c

@@ -220,7 +220,7 @@ static sctp_xmit_t sctp_packet_bundle_auth(struct sctp_packet *pkt,
 	/* See if this is an auth chunk we are bundling or if
 	 * auth is already bundled.
 	 */
-	if (chunk->chunk_hdr->type == SCTP_CID_AUTH || pkt->auth)
+	if (chunk->chunk_hdr->type == SCTP_CID_AUTH || pkt->has_auth)
 		return retval;
 
 	/* if the peer did not request this chunk to be authenticated,