Let it build with dcoppa's upcoming update to hs-X11.

Gypped from Arch Linux.

x11/xmonad/patches/patch-xmonad_cabal

@@ -0,0 +1,15 @@
+$OpenBSD: patch-xmonad_cabal,v 1.5 2012/06/19 17:51:49 kili Exp $
+
+Allow building against X11-1.6. From Arch Linux.
+
+--- xmonad.cabal.orig	Sat Nov 19 00:14:36 2011
++++ xmonad.cabal	Tue Jun 19 19:50:50 2012
+@@ -46,7 +46,7 @@ library
+         build-depends: base < 5 && >=3, containers, directory, process, filepath, extensible-exceptions
+     else
+         build-depends: base < 3
+-    build-depends: X11>=1.5.0.0 && < 1.6, mtl, unix,
++    build-depends: X11>=1.5.0.0 && < 1.7, mtl, unix,
+                    utf8-string >= 0.3 && < 0.4
+ 
+     if true