[PATCH 0/5] More rt->rt_{src,dst} removals.

After this set the number of uses of rt->rt_{src,dst} are very small.

One case to hit still will need a slight rearrangement of how we do
SRR handling, since SRR handling on input pops the nexthop and thus
creates situations where iph->daddr != rt->rt_dst and thus eliminates
the posibility of converting the rt->rt_dst access in ip_forward().

Another class of remaining cases occur in situations where we can
fetch the saddr/daddr from the inet socket.

Soon, all that will be left are the assignments and netlink dump code
cases in net/ipv4/route.c