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/misc/tewisay/default.nix

@@ -0,0 +1,35 @@
+{ lib, buildGoPackage, fetchFromGitHub, makeWrapper }:
+
+buildGoPackage rec {
+  pname = "tewisay-unstable";
+  version = "2017-04-14";
+
+  goPackagePath = "github.com/lucy/tewisay";
+
+  src = fetchFromGitHub {
+    owner = "lucy";
+    repo = "tewisay";
+    rev = "e3fc38737cedb79d93b8cee07207c6c86db4e488";
+    sha256 = "1na3xi4z90v8qydcvd3454ia9jg7qhinciy6kvgyz61q837cw5dk";
+  };
+
+  nativeBuildInputs = [ makeWrapper ];
+
+  goDeps = ./deps.nix;
+
+  postInstall = ''
+    install -D -t $out/share/tewisay/cows go/src/${goPackagePath}/cows/*.cow
+  '';
+
+  preFixup = ''
+    wrapProgram $out/bin/tewisay \
+      --prefix COWPATH : $out/share/tewisay/cows
+  '';
+
+  meta = with lib; {
+    homepage = "https://github.com/lucy/tewisay";
+    description = "Cowsay replacement with unicode and partial ansi escape support";
+    license = licenses.cc0;
+    maintainers = with maintainers; [ Madouura ];
+  };
+}