setup-hooks using addToSearchPath

I've accidentially reverted setup-hooks while merging with trunk. Correcting it.

svn path=/nixpkgs/branches/stdenv-updates/; revision=9821

pkgs/development/tools/misc/pkgconfig/builder.sh

@@ -1,10 +0,0 @@
-source $stdenv/setup
-
-postInstall() {
-    test -x $out/nix-support || mkdir $out/nix-support
-    cp $setupHook $out/nix-support/setup-hook
-}
-postInstall=postInstall
-
-genericBuild
-

pkgs/development/tools/misc/pkgconfig/default.nix

@@ -1,12 +1,11 @@
 {stdenv, fetchurl}:
 
 stdenv.mkDerivation {
-  name = "pkgconfig-0.21";
-  builder = ./builder.sh;
+  name = "pkgconfig-0.22";
   setupHook = ./setup-hook.sh;
   src = fetchurl {
-    url = http://nix.cs.uu.nl/dist/tarballs/pkg-config-0.21.tar.gz;
-    md5 = "476f45fab1504aac6697aa7785f0ab91";
+    url = http://pkgconfig.freedesktop.org/releases/pkg-config-0.22.tar.gz;
+    sha256 = "1rpb5wygmp0f8nal7y3ga4556i7hkjdslv3wdq04fj30gns621vy";
   };
 
   patches = [
@@ -19,3 +18,4 @@ stdenv.mkDerivation {
     })
   ];
 }
+

pkgs/development/tools/misc/pkgconfig/setup-hook.sh

@@ -1,7 +1,5 @@
 addPkgConfigPath () {
-    if test -d $1/lib/pkgconfig; then
-        export PKG_CONFIG_PATH="${PKG_CONFIG_PATH}${PKG_CONFIG_PATH:+:}$1/lib/pkgconfig"
-    fi
+	addToSearchPath PKG_CONFIG_PATH /lib/pkgconfig "" $1
 }
 
 envHooks=(${envHooks[@]} addPkgConfigPath)