portupgrade's library handling seems broken

[Robert Woolley]

I noticed that none of the libraries in /usr/local/lib/compat/pkg/, is
showing-up in the output of ldconfig -r. 

I had a specific problem where after a build problem  qbittorrent was
failing to start because it couldn't find libtorrent-rasterbar.so.8.
compat/pkg only had libtorrent-rasterbar.so.8.0.0 without a
libtorrent-rasterbar.so.8 symlink. Creating the link solved the
problem. 

I'm not certain, but I think that older versions of portupgrade would
have renamed libtorrent-rasterbar.so.8.0.0 to
libtorrent-rasterbar.so.8. when it was moved to compat/pkg.