Copyright and license for the ipv6.7 manual page

Copyright for ipv6.7:

This man page is Copyright (C) 2000 Andi Kleen <ak@muc.de>.

License for ipv6.7:

Permission is granted to distribute possibly modified copies
of this page provided the header is included verbatim,
and in case of nontrivial modification author and date
of the modification is added to the header.