expat: 2.2.1 -> 2.2.2

pkgs/development/libraries/expat/default.nix

···
 { stdenv, fetchurl }:
 
 stdenv.mkDerivation rec {
-  name = "expat-2.2.1";
+  name = "expat-2.2.2";
 
   src = fetchurl {
     url = "mirror://sourceforge/expat/${name}.tar.bz2";
-    sha256 = "11c8jy1wvllvlk7xdc5cm8hdhg0hvs8j0aqy6s702an8wkdcls0q";
+    sha256 = "0ik0r39ala9c6hj4kxrk933klgwkzlkbrfhvhaykx8l1rwgr2xj3";
   };
 
   outputs = [ "out" "dev" ]; # TODO: fix referrers