[PATCH 0/7] Ipv6 TCP timewait recycling support

First we start with two simple cleanups, un-typedef'ification
and a comment fixup.

Then we add the infrastructure to allow the tcp_minisocks.c
timewait recycling code able to be generic and use various
->ops

Sadly, the ipv6 timewait ops are used even for v4-mapped
addresses so we need a special check in the ipv6 timewait
getpeer implementation.  This is similar to the situation
we have in tcp_v6_hash().

Doing these changes also pointed out that our listening socket
incoming connection policy in the non-syncookies case as
being handled differently for ipv4 vs. ipv6.  This has been
rectified.  The issue is that for ipv4 we were reserving the
final 1/4 of the backlog queue to validated destinations.

In the final patch we throw the switch and implement the two
getpeer operations for ipv6, which fully enables timewait
recyling for ipv6.