tcp: cleanup static functions

tcp_fastopen_create_child() is static and should not be exported.

tcp4_gso_segment() and tcp6_gso_segment() should be static.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv4/tcp_offload.c b/net/ipv4/tcp_offload.c
index 9d7930b..3f7c2fc 100644
--- a/net/ipv4/tcp_offload.c
+++ b/net/ipv4/tcp_offload.c
@@ -29,8 +29,8 @@
 	}
 }
 
-struct sk_buff *tcp4_gso_segment(struct sk_buff *skb,
-				 netdev_features_t features)
+static struct sk_buff *tcp4_gso_segment(struct sk_buff *skb,
+					netdev_features_t features)
 {
 	if (!pskb_may_pull(skb, sizeof(struct tcphdr)))
 		return ERR_PTR(-EINVAL);