[ICSK]: Introduce reqsk_queue_prune from code in tcp_synack_timer

With this we're very close to getting all of the current TCP
refactorings in my dccp-2.6 tree merged, next changeset will export
some functions needed by the current DCCP code and then dccp-2.6.git
will be born!

Signed-off-by: Arnaldo Carvalho de Melo <acme@ghostprotocols.net>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/core/request_sock.c b/net/core/request_sock.c
index 98f0fc9..b8203de 100644
--- a/net/core/request_sock.c
+++ b/net/core/request_sock.c
@@ -52,6 +52,7 @@
 	get_random_bytes(&lopt->hash_rnd, sizeof(lopt->hash_rnd));
 	rwlock_init(&queue->syn_wait_lock);
 	queue->rskq_accept_head = queue->rskq_accept_head = NULL;
+	queue->rskq_defer_accept = 0;
 	lopt->nr_table_entries = nr_table_entries;
 
 	write_lock_bh(&queue->syn_wait_lock);