Using symlinks to save space on duplicate copies of the
/usr/share/doc/*/changelog.Debian.gz is a bit of a mess, since when
the foo-dev package is removed, the files in /usr/share/doc/libfoo/*
get removed, which means the copyright file gets removed.
So stop doing this altogether, and set up maintainer scripts to clean
up the mess so that the symlinks are removed when the packages get
upgraded.
Addresses-Debian-Bug: #905195
Signed-off-by: Theodore Ts'o <tytso@mit.edu>