libtxc_dxtn: get rid of duplicate package, clean up build script.

pkgs/development/libraries/libtxc_dxtn/default.nix

···
-{ stdenv, fetchurl, autoconf, automake, libtool, mesa }:
+{ stdenv, fetchurl, autoreconfHook, mesa }:
 
 let version = "1.0.1"; in
 
···
   name = "libtxc_dxtn-${version}";
 
   src = fetchurl {
-    url = "http://cgit.freedesktop.org/~mareko/${name}.tar.gz";
-    sha256 = "0g6lymik9cs7nbzigwzaf49fnhhfsvjanhg92wykw7rfq9zvkhvv";
+    url = "http://people.freedesktop.org/~cbrill/libtxc_dxtn/${name}.tar.bz2";
+    sha256 = "0q5fjaknl7s0z206dd8nzk9bdh8g4p23bz7784zrllnarl90saa5";
   };
 
-  buildInputs = [ autoconf automake libtool mesa ];
-
-  preConfigure = "autoreconf -vfi";
+  buildInputs = [ autoreconfHook mesa ];
 
   meta = {
     homepage = http://dri.freedesktop.org/wiki/S3TC;
+    repositories.git = git://people.freedesktop.org/~mareko/libtxc_dxtn;
   };
 }

pkgs/development/libraries/libxtc_dxtn/default.nix

···
-{ stdenv, fetchurl, mesa }:
-
-stdenv.mkDerivation rec {
-  name = "libtxc_dxtn-1.0.1";
-
-  src = fetchurl {
-    url = "http://people.freedesktop.org/~cbrill/libtxc_dxtn/${name}.tar.bz2";
-    sha256 = "0q5fjaknl7s0z206dd8nzk9bdh8g4p23bz7784zrllnarl90saa5";
-  };
-
-  NIX_CFLAGS_COMPILE = "-I ${mesa}/include";
-}

pkgs/top-level/all-packages.nix

···
 
   libxslt = callPackage ../development/libraries/libxslt { };
 
-  libxtc_dxtn = callPackage ../development/libraries/libxtc_dxtn { };
-
   libixp_for_wmii = lowPrio (import ../development/libraries/libixp_for_wmii {
     inherit fetchurl stdenv;
   });