Merge branch 'ipv6-firewire'

YOSHIFUJI Hideaki says:

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This is take 4 of supporting IPv6 over Firewire (IEEE 1394) based on
RFC3146.

Take 3->4:
- Fix receiving 1394 ARP, which comes without arp$tha.
- Remove rfc3146 unit directory on module exit.
- other minor clean-ups - minimize diffs.

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