af_iucv: use sk functions to modify sk->sk_ack_backlog

Instead of modifying sk->sk_ack_backlog directly, use respective
socket functions.

Signed-off-by: Hendrik Brueckner <brueckner@linux.vnet.ibm.com>
Signed-off-by: Ursula Braun <ursula.braun@de.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/iucv/af_iucv.c b/net/iucv/af_iucv.c
index 004134b..73ea01b 100644
--- a/net/iucv/af_iucv.c
+++ b/net/iucv/af_iucv.c
@@ -536,7 +536,7 @@
 	list_add_tail(&iucv_sk(sk)->accept_q, &par->accept_q);
 	spin_unlock_irqrestore(&par->accept_q_lock, flags);
 	iucv_sk(sk)->parent = parent;
-	parent->sk_ack_backlog++;
+	sk_acceptq_added(parent);
 }
 
 void iucv_accept_unlink(struct sock *sk)
@@ -547,7 +547,7 @@
 	spin_lock_irqsave(&par->accept_q_lock, flags);
 	list_del_init(&iucv_sk(sk)->accept_q);
 	spin_unlock_irqrestore(&par->accept_q_lock, flags);
-	iucv_sk(sk)->parent->sk_ack_backlog--;
+	sk_acceptq_removed(iucv_sk(sk)->parent);
 	iucv_sk(sk)->parent = NULL;
 	sock_put(sk);
 }