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/qrcodegen/default.nix

@@ -0,0 +1,41 @@
+{ lib
+, stdenv
+, fetchFromGitHub
+}:
+
+stdenv.mkDerivation rec {
+  pname = "qrcodegen";
+  version = "1.7.0";
+
+  src = fetchFromGitHub {
+    owner = "nayuki";
+    repo = "QR-Code-generator";
+    rev = "v${version}";
+    sha256 = "sha256-WH6O3YE/+NNznzl52TXZYL+6O25GmKSnaFqDDhRl4As=";
+  };
+
+  preBuild = ''
+    cd c/
+  '';
+
+  installPhase = ''
+    runHook preInstall
+
+    mkdir -p $out/lib $out/include/qrcodegen
+    cp libqrcodegen.a $out/lib
+    cp qrcodegen.h $out/include/qrcodegen/
+
+    runHook postInstall
+  '';
+
+  meta = with lib; {
+    homepage = "https://www.nayuki.io/page/qr-code-generator-library";
+    description = "High-quality QR Code generator library in many languages";
+    license = licenses.mit;
+    maintainers = with maintainers; [ mcbeth AndersonTorres ];
+    platforms = platforms.unix;
+    broken = stdenv.isDarwin;
+  };
+}
+# TODO: build the other languages
+# TODO: multiple outputs