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/applications/misc/vcal/default.nix

@@ -0,0 +1,37 @@
+{ stdenv, lib, fetchurl, perl }:
+
+stdenv.mkDerivation rec {
+  pname = "vcal";
+  version = "2.8";
+
+  src = fetchurl {
+    url    = "https://waynemorrison.com/software/vcal";
+    sha256 = "0jrm0jzqxb1xjp24hwbzlxsh22gjssay9gj4zszljzdm68r5afvc";
+  };
+
+  nativeBuildInputs = [ perl ]; # for pod2man
+
+  dontUnpack = true;
+  dontBuild = true;
+  installPhase = ''
+    runHook preInstall
+
+    mkdir -p $out/{bin,share/man/man1}
+    substitute ${src} $out/bin/vcal \
+      --replace /usr/bin/perl ${perl}/bin/perl
+    chmod 0755 $out/bin/*
+    pod2man --name=vcal --release=${version} ${src} > $out/share/man/man1/vcal.1
+
+    runHook postInstall
+  '';
+
+  # There are no tests
+  doCheck = false;
+
+  meta = with lib; {
+    description = "Parser for VCalendar and ICalendar files, usable from the command line";
+    homepage = "https://waynemorrison.com/software/";
+    license = licenses.asl20;
+    maintainers = with maintainers; [ peterhoeg ];
+  };
+}