uboot: (firmwareOdroidC2/C4) don't invoke patch tool, use patches = [] instead

https://github.com/NixOS/nixpkgs/blob/master/pkgs/stdenv/generic/setup.sh#L948
this can do it nicely.

Signed-off-by: Anton Arapov <anton@deadbeef.mx>

pkgs/tools/text/mecab/default.nix

@@ -0,0 +1,21 @@
+{ lib, stdenv, fetchurl, mecab-ipadic }:
+
+let
+  mecab-base = import ./base.nix { inherit fetchurl; };
+in
+stdenv.mkDerivation (mecab-base // {
+    pname = "mecab";
+    version = mecab-base.version;
+
+    postInstall = ''
+      sed -i 's|^dicdir = .*$|dicdir = ${mecab-ipadic}|' "$out/etc/mecabrc"
+    '';
+
+    meta = with lib; {
+      description = "Japanese morphological analysis system";
+      homepage = "http://taku910.github.io/mecab/";
+      license = licenses.bsd3;
+      platforms = platforms.unix;
+      maintainers = with maintainers; [ auntie ];
+    };
+})