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/networking/snmpcheck/default.nix

@@ -0,0 +1,30 @@
+{ stdenv, lib, fetchurl, ruby }:
+
+let
+  rubyEnv = ruby.withPackages (ps: [ ps.snmp ]);
+in
+stdenv.mkDerivation rec {
+  pname = "snmpcheck";
+  version = "1.9";
+  src = fetchurl {
+    url = "http://www.nothink.org/codes/snmpcheck/snmpcheck-${version}.rb";
+    sha256 = "sha256-9xkLqbgxU1uykx+M9QsbPAH8OI/Cqn9uw6ALe23Lbq0=";
+    executable = true;
+  };
+
+  dontUnpack = true;
+
+  buildInputs = [ rubyEnv.wrappedRuby ];
+
+  installPhase = ''
+    mkdir -p $out/bin
+    cp $src $out/bin/snmp-check
+  '';
+
+  meta = with lib; {
+    description = "SNMP enumerator";
+    homepage = "http://www.nothink.org/codes/snmpcheck/";
+    license = licenses.gpl3Plus;
+    maintainers = with maintainers; [ elohmeier ];
+  };
+}