ipv6: icmp: add a force_saddr param to icmp6_send()

SIT or GRE tunnels might want to translate an IPV4 address
into a v4mapped one when translating ICMP to ICMPv6.

This patch adds the parameter to icmp6_send() but
does not change icmpv6_send() signature.

Signed-off-by: Eric Dumazet <edumazet@google.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/ip6_icmp.c b/net/ipv6/ip6_icmp.c
index 14dacc5..713676f 100644
--- a/net/ipv6/ip6_icmp.c
+++ b/net/ipv6/ip6_icmp.c
@@ -39,7 +39,7 @@
 
 	if (!send)
 		goto out;
-	send(skb, type, code, info);
+	send(skb, type, code, info, NULL);
 out:
 	rcu_read_unlock();
 }