[NET]: Revert incorrect accept queue backlog changes.

This reverts two changes:

8488df894d05d6fa41c2bd298c335f944bb0e401
248f06726e866942b3d8ca8f411f9067713b7ff8

A backlog value of N really does mean allow "N + 1" connections
to queue to a listening socket.  This allows one to specify
"0" as the backlog and still get 1 connection.

Noticed by Gerrit Renker and Rick Jones.

Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/sock.h b/include/net/sock.h
index 849c7df..2c7d60c 100644
--- a/include/net/sock.h
+++ b/include/net/sock.h
@@ -426,7 +426,7 @@
 
 static inline int sk_acceptq_is_full(struct sock *sk)
 {
-	return sk->sk_ack_backlog >= sk->sk_max_ack_backlog;
+	return sk->sk_ack_backlog > sk->sk_max_ack_backlog;
 }
 
 /*