* sys/netinet6/nd6.c: recover backward binary compatibility for   SIOCGIFINFO_IN6. * openbsd/sys/netinet/udp_usrreq.c: remove IPv6 cases from udp_output()   to simplify it and make it easier to audit it (sync with openbsd-   current).
* sys/netinet6/nd6.c: recover backward binary compatibility for
  SIOCGIFINFO_IN6.
* openbsd/sys/netinet/udp_usrreq.c: remove IPv6 cases from udp_output()
  to simplify it and make it easier to audit it (sync with openbsd-
  current).

MarginC/kame,MarginC/kame,MarginC/kame,MarginC/kame,MarginC/kame,MarginC/kame,MarginC/kame