route6d spring cleanup

route6d spring cleanup

Various tweaks and fixes:
- nuke util.h, not needed since pidfile(3) went away
- nuke the rrt_same member of struct riprt, "future use" since import
- mark rtdexit as __dead
- nuke progname handling
- fix pid handling: cache the pid *after* calling daemon(3)
- nuke setting rtm_pid.  The kernel is responsible for setting this
  in routing messages.
- nuke the useless myseq variable

ok florian@ benno@ millert@ deraadt@ renato@