hedgewars: add missing patch

pkgs/games/hedgewars/21eb5b79072b147d0a9b7fafca98501e7056c834.patch

@@ -0,0 +1,36 @@
+From 21eb5b79072b147d0a9b7fafca98501e7056c834 Mon Sep 17 00:00:00 2001
+From: koda <vittorio.giovara@gmail.com>
+Date: Tue, 2 Jun 2015 19:51:04 +0100
+Subject: [PATCH] Fix building hedgewars-server
+
+---
+ gameServer/CoreTypes.hs           | 2 +-
+ gameServer/hedgewars-server.cabal | 2 +-
+ 2 files changed, 2 insertions(+), 2 deletions(-)
+
+diff --git a/gameServer/CoreTypes.hs b/gameServer/CoreTypes.hs
+index 553e722..2c75153 100644
+--- a/gameServer/CoreTypes.hs
++++ b/gameServer/CoreTypes.hs
+@@ -38,7 +38,7 @@ import RoomsAndClients
+ instance NFData B.ByteString
+ #endif
+ 
+-instance NFData (Chan a)
++instance NFData (Chan a) where rnf a  = ()
+ 
+ instance NFData Action where
+     rnf (AnswerClients chans msg) = chans `deepseq` msg `deepseq` ()
+diff --git a/gameServer/hedgewars-server.cabal b/gameServer/hedgewars-server.cabal
+index 122f2ef..f36a190 100644
+--- a/gameServer/hedgewars-server.cabal
++++ b/gameServer/hedgewars-server.cabal
+@@ -33,7 +33,7 @@ Executable hedgewars-server
+     utf8-string,
+     SHA,
+     entropy,
+-    zlib
++    zlib >= 0.5.3 && < 0.6
+ 
+   if !os(windows)
+     build-depends: unix