vmxnet3: use new helper tcp_v6_gso_csum_prep

Use new helper tcp_v6_gso_csum_prep in additional network drivers.
Signed-off-by: Heiner Kallweit <hkallweit1@gmail.com>
Signed-off-by: David S. Miller <davem@davemloft.net>

drivers/net/vmxnet3/vmxnet3_drv.c

@@ -942,10 +942,7 @@ vmxnet3_prepare_tso(struct sk_buff *skb,
 		tcph->check = ~csum_tcpudp_magic(iph->saddr, iph->daddr, 0,
 						 IPPROTO_TCP, 0);
 	} else if (ctx->ipv6) {
-		struct ipv6hdr *iph = ipv6_hdr(skb);
-
-		tcph->check = ~csum_ipv6_magic(&iph->saddr, &iph->daddr, 0,
-					       IPPROTO_TCP, 0);
+		tcp_v6_gso_csum_prep(skb);
 	}
 }