sys: Remove $FreeBSD$: two-line .h pattern

Remove /^\s*\*\n \*\s+\$FreeBSD\$$\n/

Implement flowid calculation for outbound connections to balance
connections over multiple paths.

Multipath routing relies on mbuf flowid data for both transit
and outbound traffic. Current code fills mbuf flowid from inp_flowid
for connection-oriented sockets. However, inp_flowid is currently
not calculated for outbound connections.

This change creates simple hashing functions and starts calculating hashes
for TCP,UDP/UDP-Lite and raw IP if multipath routes are present in the
system.

Reviewed by: glebius (previous version),ae
Differential Revision: https://reviews.freebsd.org/D26523

Implement RSS hashing/re-hashing for IPv6 ingress packets.

This mirrors the basic IPv4 implementation - IPv6 packets under RSS
now are checked for a correct RSS hash and if one isn't provided,
it's done in software.

This only handles the initial receive - it doesn't yet handle
reinjecting / rehashing packets after being decapsulated from
various tunneling setups. That'll come in some follow-up work.

For non-RSS users, this is almost a giant no-op.

It does change a couple of ipv6 methods to use const mbuf * instead of
mbuf * but it doesn't have any functional changes.

So, the following now occurs:

* If the NIC doesn't do any RSS hashing, it's all done in software.
Single-queue, non-RSS NICs will now have the RX path distributed
into multiple receive netisr queues.

* If the NIC provides the wrong hash (eg only IPv6 hash when we needed
an IPv6 TCP hash, or IPv6 UDP hash when we expected IPv6 hash)
then the hash is recalculated.

* .. if the hash is recalculated, it'll end up being injected into
the correct netisr queue for v6 processing.

Submitted by: Tiwei Bie <btw@mail.ustc.edu.cn>
Differential Revision: https://reviews.freebsd.org/D3504

Implement the IPv6 RSS software hash function.

This isn't yet linked into the receive/transmit paths anywhere just yet.

This is part of a GSoC 2015 project.

Submitted by: Tiwei Bie <btw@mail.ustc.edu.cn>
Reviewed by: hiren, gnn
Differential Revision: https://reviews.freebsd.org/D3423

Refactor / restructure the RSS code into generic, IPv4 and IPv6 specific
bits.

The motivation here is to eventually teach netisr and potentially
other networking subsystems a bit more about how RSS work queues / buckets
are configured so things have a hope of auto-configuring in the future.

* net/rss_config.[ch] takes care of the generic bits for doing
configuration, hash function selection, etc;
* topelitz.[ch] is now in net/ rather than netinet/;
* (and would be in libkern if it didn't directly include RSS_KEYSIZE;
that's a later thing to fix up.)
* netinet/in_rss.[ch] now just contains the IPv4 specific methods;
* and netinet/in6_rss.[ch] now just contains the IPv6 specific methods.

This should have no functional impact on anyone currently using
the RSS support.

Differential Revision: D1383
Reviewed by: gnn, jfv (intel driver bits)