sctp: add support for generating stream reconf add incoming/outgoing streams request chunk

This patch is to define Add Incoming/Outgoing Streams Request
Parameter described in rfc6525 section 4.5 and 4.6. They can
be in one same chunk trunk as rfc6525 section 3.1-7 describes,
so make them in one function.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Acked-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/sctp.h b/include/linux/sctp.h
index 71c0d41..b055788 100644
--- a/include/linux/sctp.h
+++ b/include/linux/sctp.h
@@ -742,4 +742,11 @@ struct sctp_strreset_tsnreq {
 	__u32 request_seq;
 };
 
+struct sctp_strreset_addstrm {
+	sctp_paramhdr_t param_hdr;
+	__u32 request_seq;
+	__u16 number_of_streams;
+	__u16 reserved;
+};
+
 #endif /* __LINUX_SCTP_H__ */