[NETNS][IPV6]: Make icmpv6_time sysctl per namespace.

This patch moves the icmpv6_time sysctl to the network namespace
structure.

Because the ipv6 protocol is not yet per namespace, the variable is
accessed relatively to the initial network namespace.

Signed-off-by: Daniel Lezcano <dlezcano@fr.ibm.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/ipv6/af_inet6.c b/net/ipv6/af_inet6.c
index 3aea84a..218b8b3 100644
--- a/net/ipv6/af_inet6.c
+++ b/net/ipv6/af_inet6.c
@@ -734,6 +734,7 @@
 	net->ipv6.sysctl.ip6_rt_gc_elasticity = 9;
 	net->ipv6.sysctl.ip6_rt_mtu_expires = 10*60*HZ;
 	net->ipv6.sysctl.ip6_rt_min_advmss = IPV6_MIN_MTU - 20 - 40;
+	net->ipv6.sysctl.icmpv6_time = 1*HZ;
 	ipv6_frag_sysctl_init(net);
 
 	return 0;