add glu library from mesa, needed e.g. for SDL

It provides the includes/GL/glu.h file.

pkgs/development/libraries/mesa-glu/default.nix

@@ -0,0 +1,18 @@
+{ stdenv, fetchurl, pkgconfig, mesa }:
+
+stdenv.mkDerivation rec {
+  name = "glu-9.0.0";
+
+  src = fetchurl {
+    url = "ftp://ftp.freedesktop.org/pub/mesa/glu/${name}.tar.bz2";
+    sha256 = "04nzlil3a6fifcmb95iix3yl8mbxdl66b99s62yzq8m7g79x0yhz";
+  };
+
+  buildInputs = [ pkgconfig mesa ];
+
+  meta = {
+    description = "OpenGL utility library";
+    homepage = http://cgit.freedesktop.org/mesa/glu/;
+    license = "bsd"; # SGI-B-2.0, which seems BSD-like
+  };
+}

pkgs/top-level/all-packages.nix

@@ -4597,6 +4597,8 @@ let
 
   mesa = callPackage ../development/libraries/mesa { };
 
+  mesa_glu = callPackage ../development/libraries/mesa-glu { };
+
   metaEnvironment = recurseIntoAttrs (let callPackage = newScope pkgs.metaEnvironment; in rec {
     sdfLibrary    = callPackage ../development/libraries/sdf-library { aterm = aterm28; };
     toolbuslib    = callPackage ../development/libraries/toolbuslib { aterm = aterm28; inherit (windows) w32api; };