libutil.so version bumped, but no compat lib yet

After rebuilding a -CURRENT box today and removing some old cruft, as
I usually do, I noticed that libutil.so had been bumped to version 4,
although there wasn't any version 3 in /usr/lib/compat yet.

This bump was done quite recently, Wed Nov 12 21:56:07 2003 UTC.  I'm
not sure if it was an oversight to leave out installing a compat lib,
or is the policy in this case "just rebuild almost all your ports,
this is -CURRENT, after all" ? :)  (It turns out that quite a lot of
them depend on libutil.so.3 ...)

If it's needed, I'll shoot in a nice PR.  There's probably a good copy
of a libutil.so.3 binary to be found on the 5.1-RELEASE CD, or else
I'll just keep using my old one. :)