ipv6: fix inet6_csk_xmit()

We should provide to inet6_csk_route_socket a struct flowi6 pointer,
so that net6_csk_xmit() works correctly instead of sending garbage.

Also add some consts

Signed-off-by: Eric Dumazet <edumazet@google.com>
Reported-by: Yuchung Cheng <ycheng@google.com>
Cc: Neal Cardwell <ncardwell@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/include/linux/ipv6.h b/include/linux/ipv6.h
index bc6c8fd..379e433 100644
--- a/include/linux/ipv6.h
+++ b/include/linux/ipv6.h
@@ -299,9 +299,9 @@
 	struct in6_addr 	rcv_saddr;
 	struct in6_addr		daddr;
 	struct in6_pktinfo	sticky_pktinfo;
-	struct in6_addr		*daddr_cache;
+	const struct in6_addr		*daddr_cache;
 #ifdef CONFIG_IPV6_SUBTREES
-	struct in6_addr		*saddr_cache;
+	const struct in6_addr		*saddr_cache;
 #endif
 
 	__be32			flow_label;