Merge branch 'redirect_via_sock'

As described in my patch series from the other day, we need to
rearrange redirect handling so that the local initiators of packets
(sockets, tunnels, xfrms, etc.) that implement the protocols compute
the route and pass this down into the ipv4/ipv6 routing code.

These changes here do so by implementing a new dst_ops->redirect
method.

No more do we have this funny code that tries several different sets
of routing keys to try and figure out which route the redirect should
actually be applied to.

No more do we have the problem wherein TOS rewriting causes problems
for us.

Signed-off-by: David S. Miller <davem@davemloft.net>