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/os-specific/linux/tunctl/default.nix

@@ -0,0 +1,24 @@
+{lib, stdenv, fetchurl}:
+
+stdenv.mkDerivation rec {
+  pname = "tunctl";
+  version = "1.5";
+
+  src = fetchurl {
+    url = "mirror://sourceforge/tunctl/tunctl-${version}.tar.gz";
+    sha256 = "aa2a6c4cc6bfacb11e0d9f62334a6638a0d435475c61230116f00b6af8b14fff";
+  };
+
+  makeFlags = [ "tunctl" ];
+  installPhase = ''
+    mkdir -p $out/bin
+    cp tunctl $out/bin
+  '';
+
+  meta = {
+    homepage = "http://tunctl.sourceforge.net/";
+    description = "Utility to set up and maintain TUN/TAP network interfaces";
+    license = lib.licenses.gpl2;
+    platforms = lib.platforms.linux;
+  };
+}