[TCP]: Don't set SKB owner in tcp_transmit_skb().

The data itself is already charged to the SKB, doing
the skb_set_owner_w() just generates a lot of noise and
extra atomics we don't really need.

Lmbench improvements on lat_tcp are minimal:

before:
TCP latency using localhost: 23.2701 microseconds
TCP latency using localhost: 23.1994 microseconds
TCP latency using localhost: 23.2257 microseconds

after:
TCP latency using localhost: 22.8380 microseconds
TCP latency using localhost: 22.9465 microseconds
TCP latency using localhost: 22.8462 microseconds

Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/net/inet6_connection_sock.h b/include/net/inet6_connection_sock.h
index f13ddc2..16aa96a 100644
--- a/include/net/inet6_connection_sock.h
+++ b/include/net/inet6_connection_sock.h
@@ -38,5 +38,5 @@
 
 extern void inet6_csk_addr2sockaddr(struct sock *sk, struct sockaddr *uaddr);
 
-extern int inet6_csk_xmit(struct sk_buff *skb, int ipfragok);
+extern int inet6_csk_xmit(struct sk_buff *skb, struct sock *sk, int ipfragok);
 #endif /* _INET6_CONNECTION_SOCK_H */