continuation of #109595
pkgconfig was aliased in 2018, however, it remained in
all-packages.nix due to its wide usage. This cleans
up the remaining references to pkgs.pkgsconfig and
moves the entry to aliases.nix.
python3Packages.pkgconfig remained unchanged because
it's the canonical name of the upstream package
on pypi.
psppire needs to be wrapped so that it will work outside of GNOME
desktop. We provide hicolor-icon-theme & gsettings-desktop-schemas.
Note that at runtime, I still get this error:
- Cannot create a converter for `IBM864' to `UTF-8': Invalid argument
Possibly a locale issue.
Fixes#40558
