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/grex/default.nix

@@ -0,0 +1,35 @@
+{ lib, stdenv
+, fetchFromGitHub
+, fetchpatch
+, rustPlatform
+, Security
+, libiconv
+}:
+
+rustPlatform.buildRustPackage rec {
+  pname = "grex";
+  version = "1.3.0";
+
+  cargoSha256 = "sha256-zNwTk4RcTv2dGbKWelOPSvasBmj7tnjLhQ0DZhZ9hxk=";
+
+  src = fetchFromGitHub {
+    owner = "pemistahl";
+    repo = pname;
+    rev = "v${version}";
+    sha256 = "sha256-NMz35jgd7XPemVdA8nol2H6cgWD3yEPh0FEMPw8kgKQ=";
+  };
+
+  buildInputs = lib.optionals stdenv.isDarwin [ Security ];
+
+  doInstallCheck = true;
+  installCheckPhase = ''
+    $out/bin/grex --help > /dev/null
+  '';
+
+  meta = with lib; {
+    description = "A command-line tool for generating regular expressions from user-provided test cases";
+    homepage = "https://github.com/pemistahl/grex";
+    license = licenses.asl20;
+    maintainers = with maintainers; [ SuperSandro2000 ];
+  };
+}