nkf: pull upstream fix for parallel build failure

Without the change parallel build fails as:

    cp -f nkf ...-nkf-2.1.5/bin/
    mkdir ...-nkf-2.1.5/man/ja
    mkdir: cannot create directory '...-nkf-2.1.5/man/ja': No such file or directory

pkgs/tools/text/nkf/default.nix

@@ -1,4 +1,4 @@
-{ lib, stdenv, fetchurl }:
+{ lib, stdenv, fetchurl, fetchpatch }:
 
 stdenv.mkDerivation rec {
   pname = "nkf";
@@ -9,6 +9,15 @@ stdenv.mkDerivation rec {
     sha256 = "0i5dbcb9aipwr8ym4mhvgf1in3frl6y8h8x96cprz9s7b11xz9yi";
   };
 
+  patches = [
+    # Pull upstream fix for parllel build failures
+    (fetchpatch {
+      name = "parallel-install.patch";
+      url = "http://git.osdn.net/view?p=nkf/nkf.git;a=patch;h=9ccff5975bec7963e591e042e1ab1139252a4dc9";
+      sha256 = "00f0x414gfch650b20w0yj5x2bd67hchmadl7v54lk3vdgkc6jwj";
+    })
+  ];
+
   makeFlags = [ "prefix=$(out)" ];
 
   meta = {