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/exempi/default.nix

@@ -0,0 +1,29 @@
+{ lib, stdenv, fetchurl, fetchpatch, expat, zlib, boost, libiconv, darwin }:
+
+stdenv.mkDerivation rec {
+  pname = "exempi";
+  version = "2.5.1";
+
+  src = fetchurl {
+    url = "https://libopenraw.freedesktop.org/download/${pname}-${version}.tar.bz2";
+    sha256 = "07i29xmg8bqriviaf4vi1mwha4lrw85kfla29cfym14fp3z8aqa0";
+  };
+
+  configureFlags = [
+    "--with-boost=${boost.dev}"
+  ] ++ lib.optionals (!doCheck) [
+    "--enable-unittest=no"
+  ];
+
+  buildInputs = [ expat zlib boost ]
+    ++ lib.optionals stdenv.isDarwin [ libiconv darwin.apple_sdk.frameworks.CoreServices ];
+
+  doCheck = stdenv.isLinux && stdenv.is64bit;
+
+  meta = with lib; {
+    description = "An implementation of XMP (Adobe's Extensible Metadata Platform)";
+    homepage = "https://libopenraw.freedesktop.org/wiki/Exempi/";
+    platforms = platforms.linux ++ platforms.darwin;
+    license = licenses.bsd3;
+  };
+}