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/development/libraries/unicorn/default.nix

@@ -0,0 +1,29 @@
+{ lib, stdenv
+, fetchFromGitHub
+, pkg-config
+, cmake
+, IOKit
+}:
+
+stdenv.mkDerivation rec {
+  pname = "unicorn";
+  version = "2.0.0-rc5";
+
+  src = fetchFromGitHub {
+    owner = "unicorn-engine";
+    repo = pname;
+    rev = version;
+    sha256 = "1q9k8swnq4qsi54zdfaap69z56w3yj4n4ggm9pscmmmr69nply5f";
+  };
+
+  nativeBuildInputs = [ pkg-config cmake ];
+  buildInputs = lib.optionals stdenv.isDarwin [ IOKit ];
+
+  meta = with lib; {
+    description = "Lightweight multi-platform CPU emulator library";
+    homepage = "https://www.unicorn-engine.org";
+    license = licenses.gpl2Only;
+    platforms = platforms.unix;
+    maintainers = with maintainers; [ thoughtpolice luc65r ];
+  };
+}