expat: 2.1.1 -> 2.2.0

security patches have been integrated upstream

pkgs/development/libraries/expat/default.nix

@@ -1,11 +1,11 @@
 { stdenv, fetchurl }:
 
 stdenv.mkDerivation rec {
-  name = "expat-2.1.1";
+  name = "expat-2.2.0";
 
   src = fetchurl {
     url = "mirror://sourceforge/expat/${name}.tar.bz2";
-    sha256 = "0ryyjgvy7jq0qb7a9mhc1giy3bzn56aiwrs8dpydqngplbjq9xdg";
+    sha256 = "1zq4lnwjlw8s9mmachwfvfjf2x3lk24jm41746ykhdcvs7r0zrfr";
   };
 
   outputs = [ "dev" "out" ]; # TODO: fix referrers
@@ -15,8 +15,6 @@ stdenv.mkDerivation rec {
 
   outputMan = "dev"; # tiny page for a dev tool
 
-  patches = [ ./CVE-2015-1283-refix.patch ./CVE-2016-0718-v2-2-1.patch ];
-
   doCheck = true;
 
   meta = with stdenv.lib; {