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/devmem2/default.nix

@@ -0,0 +1,29 @@
+{ lib, stdenv, fetchurl }:
+
+stdenv.mkDerivation {
+  pname = "devmem2";
+  version = "unstable-2004-08-05";
+
+  src = fetchurl {
+    urls = [
+      "http://lartmaker.nl/lartware/port/devmem2.c"
+      "https://raw.githubusercontent.com/hackndev/tools/7ed212230f8fbb1da3424a15ee88de3279bf96ec/devmem2.c"
+    ];
+    sha256 = "14f1k7v6i1yaxg4xcaaf5i4aqn0yabba857zjnbg9wiymy82qf7c";
+  };
+
+  hardeningDisable = [ "format" ];  # fix compile error
+
+  buildCommand = ''
+    $CC "$src" -o devmem2
+    install -D devmem2 "$out/bin/devmem2"
+  '';
+
+  meta = with lib; {
+    description = "Simple program to read/write from/to any location in memory";
+    homepage = "http://lartmaker.nl/lartware/port/";
+    license = licenses.gpl2Plus;
+    platforms = platforms.linux;
+    maintainers = with maintainers; [ bjornfor ];
+  };
+}