[SCTP]: Add SENTINEL to SCTP MIB stats

Add SNMP_MIB_SENTINEL to the definition of the sctp_snmp_list so that
the output routine in proc correctly terminates. This was causing some
problems running on ia64 systems.

Signed-off-by: Vlad Yasevich <[e-mail]>
Signed-off-by: David S. Miller <[e-mail]>

net/sctp/proc.c

···
 	SNMP_MIB_ITEM("SctpReasmUsrMsgs", SCTP_MIB_REASMUSRMSGS),
 	SNMP_MIB_ITEM("SctpOutSCTPPacks", SCTP_MIB_OUTSCTPPACKS),
 	SNMP_MIB_ITEM("SctpInSCTPPacks", SCTP_MIB_INSCTPPACKS),
+	SNMP_MIB_SENTINEL
 };
 
 /* Return the current value of a particular entry in the mib by adding its