added icu-i18n mapping

[paumr]

this mapping should solve build-problems with https://github.com/haskell/text-icu

[michaelpj]

Just checking, but you're using a haskell.nix that contains #1395, right?

[paumr]

Hi,
yes, this PR was included in my pinned state.
However if you add text-icu as a cabal dependency this error gets thrown:

error: The pkg-conf packages does not contain the package: icu-i18n (pkg-conf dependency).
       You may need to augment the pkg-conf package mapping in haskell.nix so that it can be found.

Mentioned PR would have fixed this issue if this line:
pkgconfPkgs = import ./lib/pkgconf-nixpkgs-map.nix pkgs;

would be something similair to this:

        pkgconfPkgs = import ./lib/pkgconf-nixpkgs-map.nix (import ./lib/system-pkgs.nix pkgs);

[michaelpj]

Great, just checking. If you're still seeing complaints about it then this does sound like the right fix.