sctp: add support for generating add stream change event notification

This patch is to add Stream Change Event described in rfc6525
section 6.1.3.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/sctp/ulpevent.h b/include/net/sctp/ulpevent.h
index 2ab7ed4..1060494 100644
--- a/include/net/sctp/ulpevent.h
+++ b/include/net/sctp/ulpevent.h
@@ -136,6 +136,10 @@ struct sctp_ulpevent *sctp_ulpevent_make_assoc_reset_event(
 	const struct sctp_association *asoc, __u16 flags,
 	 __u32 local_tsn, __u32 remote_tsn, gfp_t gfp);
 
+struct sctp_ulpevent *sctp_ulpevent_make_stream_change_event(
+	const struct sctp_association *asoc, __u16 flags,
+	__u32 strchange_instrms, __u32 strchange_outstrms, gfp_t gfp);
+
 void sctp_ulpevent_read_sndrcvinfo(const struct sctp_ulpevent *event,
 				   struct msghdr *);
 void sctp_ulpevent_read_rcvinfo(const struct sctp_ulpevent *event,