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/dtach/default.nix

@@ -0,0 +1,35 @@
+{ lib, stdenv, fetchurl }:
+
+stdenv.mkDerivation rec {
+  pname = "dtach";
+  version = "0.9";
+
+  src = fetchurl {
+    url = "mirror://sourceforge/project/dtach/dtach/${version}/${pname}-${version}.tar.gz";
+    sha256 = "1wwj2hlngi8qn2pisvhyfxxs8gyqjlgrrv5lz91w8ly54dlzvs9j";
+  };
+
+  installPhase = ''
+    mkdir -p $out/bin
+    cp dtach $out/bin/dtach
+  '';
+
+  meta = {
+    homepage = "http://dtach.sourceforge.net/";
+    description = "A program that emulates the detach feature of screen";
+
+    longDescription = ''
+      dtach is a tiny program that emulates the detach feature of
+      screen, allowing you to run a program in an environment that is
+      protected from the controlling terminal and attach to it later.
+      dtach does not keep track of the contents of the screen, and
+      thus works best with programs that know how to redraw
+      themselves.
+    '';
+
+    license = lib.licenses.gpl2Plus;
+
+    platforms = lib.platforms.unix;
+    maintainers = [ ];
+  };
+}