[IPV6]: Always pass a valid nl_info to inet6_rt_notify.

This makes the code in the inet6_rt_notify more straightforward and provides
groud for namespace passing.

Signed-off-by: Denis V. Lunev <den@openvz.org>
Signed-off-by: David S. Miller <davem@davemloft.net>

diff --cc net/ipv6/ip6_fib.c
Simple merge

diff --cc net/ipv6/route.c
Simple merge