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/virtualization/mininet/default.nix

@@ -0,0 +1,51 @@
+{ stdenv, lib, fetchFromGitHub
+, which
+, python3
+, help2man
+}:
+
+let
+  pyEnv = python3.withPackages(ps: [ ps.setuptools ]);
+in
+stdenv.mkDerivation rec {
+  pname = "mininet";
+  version = "2.3.0";
+
+  outputs = [ "out" "py" ];
+
+  src = fetchFromGitHub {
+    owner = "mininet";
+    repo = "mininet";
+    rev = version;
+    sha256 = "sha256-bCppmeB+zQMKTptnzhsXtl72XJXU3USo7cQgP1Z6SrY=";
+  };
+
+  buildFlags = [ "mnexec" ];
+  makeFlags = [ "PREFIX=$(out)" ];
+
+  pythonPath = [ python3.pkgs.setuptools ];
+  nativeBuildInputs = [ help2man ];
+
+  propagatedBuildInputs = [ python3 which ];
+
+  installTargets = [ "install-mnexec" "install-manpages" ];
+
+  preInstall = ''
+    mkdir -p $out $py
+    # without --root, install fails
+    ${pyEnv.interpreter} setup.py install --root="/" --prefix=$py
+  '';
+
+  doCheck = false;
+
+
+  meta = with lib; {
+    description = "Emulator for rapid prototyping of Software Defined Networks";
+    license = {
+      fullName = "Mininet 2.3.0 License";
+    };
+    platforms = platforms.linux;
+    homepage = "https://github.com/mininet/mininet";
+    maintainers = with maintainers; [ teto ];
+  };
+}