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/opentimestamps-client/default.nix

@@ -0,0 +1,26 @@
+{ lib, buildPythonApplication, fetchFromGitHub, isPy3k
+, opentimestamps, appdirs, GitPython, pysocks, fetchpatch, git
+}:
+
+buildPythonApplication rec {
+  pname = "opentimestamps-client";
+  version = "0.7.0";
+  disabled = (!isPy3k);
+
+  # We can't use the pypi source because it doesn't include README.md which is
+  # needed in setup.py
+  src = fetchFromGitHub {
+    owner = "opentimestamps";
+    repo = "opentimestamps-client";
+    rev = "opentimestamps-client-v${version}";
+    sha256 = "1aiq9cwr40md54swzm7wkwj0h65psxmvj2japvw79s9x0pp8iwqs";
+  };
+
+  propagatedBuildInputs = [ opentimestamps appdirs GitPython pysocks ];
+
+  meta = {
+    description = "Command-line tool to create and verify OpenTimestamps proofs";
+    homepage = "https://github.com/opentimestamps/opentimestamps-client";
+    license = lib.licenses.lgpl3;
+  };
+}