[TCP]: Fix tcp_v4_send_synack() comment

Signed-off-by: NKris Katterjohn <katterjohn@gmail.com>
Signed-off-by: NDavid S. Miller <davem@davemloft.net>

net/ipv4/tcp_ipv4.c

@@ -719,7 +719,7 @@ static void tcp_v4_reqsk_send_ack(struct sk_buff *skb,
 }
 
 /*
- *	Send a SYN-ACK after having received an ACK.
+ *	Send a SYN-ACK after having received a SYN.
  *	This still operates on a request_sock only, not on a big
  *	socket.
  */