sctp: remove the dead field of sctp_transport

After we use refcnt to check if transport is alive, the dead can be
removed from sctp_transport.

The traversal of transport_addr_list in procfs dump is using
list_for_each_entry_rcu, no need to check if it has been freed.

sctp_generate_t3_rtx_event and sctp_generate_heartbeat_event is
protected by sock lock, it's not necessary to check dead, either.
also, the timers are cancelled when sctp_transport_free() is
called, that it doesn't wait for refcnt to reach 0 to cancel them.

Signed-off-by: Xin Long <lucien.xin@gmail.com>
Signed-off-by: Marcelo Ricardo Leitner <marcelo.leitner@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/sctp/structs.h b/include/net/sctp/structs.h
index 344da04..205630b 100644
--- a/include/net/sctp/structs.h
+++ b/include/net/sctp/structs.h
@@ -756,7 +756,6 @@
 
 	/* Reference counting. */
 	atomic_t refcnt;
-	__u32	 dead:1,
 		/* RTO-Pending : A flag used to track if one of the DATA
 		 *		chunks sent to this address is currently being
 		 *		used to compute a RTT. If this flag is 0,
@@ -766,7 +765,7 @@
 		 *		calculation completes (i.e. the DATA chunk
 		 *		is SACK'd) clear this flag.
 		 */
-		 rto_pending:1,
+	__u32	rto_pending:1,
 
 		/*
 		 * hb_sent : a flag that signals that we have a pending