busybox: fix build by adding a missing <sys/resource.h> include

This patch is going to be in the next release: http://lists.busybox.net/pipermail/busybox/2012-May/077766.html

pkgs/os-specific/linux/busybox/default.nix

@@ -44,6 +44,9 @@ stdenv.mkDerivation rec {
     sha256 = "10k8kgrprll9hxfm9gc3jl7kkq79g6l2pygn5snqwqg5v80zy4zb";
   };
 
+  # Remove this patch after the next busybox update.
+  patches = [ ./include-missing-sys-resource-header.patch ];
+
   configurePhase = ''
     make defconfig
     ${configParser}

pkgs/os-specific/linux/busybox/include-missing-sys-resource-header.patch

@@ -0,0 +1,12 @@
+diff --git a/include/libbb.h b/include/libbb.h
+index f12800f..e7806c2 100644
+--- a/include/libbb.h
++++ b/include/libbb.h
+@@ -40,6 +40,7 @@
+ #include <sys/poll.h>
+ #include <sys/ioctl.h>
+ #include <sys/mman.h>
++#include <sys/resource.h>
+ #include <sys/socket.h>
+ #include <sys/stat.h>
+ #include <sys/time.h>