Fixes the evaluation of packages in pkgs/os-specific/windows that
weren't updated to include a new lib parameter after the refactor from
stdenv.lib -> lib (#109490).
I originally only intended this change to fix
`pkgsCross.mingw32.buildPackages.gcc` & `pkgsCross.mingwW64.buildPackages.gcc`
to support building wine with `mingwSupport`, but I noticed this was
an issue for all updated windows packages. Most of these other
packages fail to build for other reasons.
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.
This is primarily going to be used for vmTools.runInWindowsVM, but in
theory, it could also work with Nix on CygWin which I haven't tested.
Signed-off-by: aszlig <aszlig@redmoonstudios.org>