This was incorrect, since route might no longer be valid at that point.

rolling back:

Wed Nov  5 00:49:19 CET 2008  Juliusz Chroboczek <jch@pps.jussieu.fr>
  * Factor out common code in flushupdates.

    M ./message.c -7 +6

Remove tracking of time, only timeouts remain.

This makes multi-interface nodes less noisy.

We now accept unfeasible updates when the source hasn't changed, just don't
update the route's timestamp.  This makes it more likely that we have
up-to-date information while still avoiding loops.