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/cowsay/default.nix

@@ -0,0 +1,47 @@
+{ lib, stdenv, perl, installShellFiles, fetchFromGitHub }:
+
+stdenv.mkDerivation rec {
+  pname = "cowsay";
+  version = "3.04";
+
+  src = fetchFromGitHub {
+    owner = "tnalpgge";
+    repo = "rank-amateur-cowsay";
+    rev = "cowsay-${version}";
+    sha256 = "sha256-9jCaQ6Um6Nl9j0/urrMCRcsGeubRN3VWD3jDM/AshRg=";
+  };
+
+  buildInputs = [ perl ];
+
+  nativeBuildInputs = [ installShellFiles ];
+
+  # overriding buildPhase because we don't want to use the install.sh script
+  buildPhase = ''
+    runHook preBuild;
+    substituteInPlace cowsay --replace "%BANGPERL%" "!${perl}/bin/perl" \
+      --replace "%PREFIX%" "$out"
+    runHook postBuild;
+  '';
+
+  installPhase = ''
+    runHook preInstall
+    install -Dm755 cowsay $out/bin/cowsay
+    ln -s $out/bin/cowsay $out/bin/cowthink
+
+    installManPage cowsay.1
+    ln -s $man/share/man/man1/cowsay.1.gz $man/share/man/man1/cowthink.1.gz
+
+    install -Dm644 cows/* -t $out/share/cows/
+    runHook postInstall
+  '';
+
+  outputs = [ "out" "man" ];
+
+  meta = with lib; {
+    description = "A program which generates ASCII pictures of a cow with a message";
+    homepage = "https://github.com/tnalpgge/rank-amateur-cowsay";
+    license = licenses.gpl3Only;
+    platforms = platforms.all;
+    maintainers = [ maintainers.rob ];
+  };
+}