x25: use limited socket backlog

Make x25 adapt to the limited socket backlog change.

Cc: Andrew Hendry <andrew.hendry@gmail.com>
Signed-off-by: Zhu Yi <yi.zhu@intel.com>
Acked-by: Eric Dumazet <eric.dumazet@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/x25/x25_dev.c b/net/x25/x25_dev.c
index 3e1efe5..a9da0dc 100644
--- a/net/x25/x25_dev.c
+++ b/net/x25/x25_dev.c
@@ -53,7 +53,7 @@
 		if (!sock_owned_by_user(sk)) {
 			queued = x25_process_rx_frame(sk, skb);
 		} else {
-			sk_add_backlog(sk, skb);
+			queued = !sk_add_backlog_limited(sk, skb);
 		}
 		bh_unlock_sock(sk);
 		sock_put(sk);