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/servers/mail/dkimproxy/default.nix

@@ -0,0 +1,33 @@
+{ lib, stdenv, perlPackages, fetchurl }:
+
+stdenv.mkDerivation rec {
+  pname = "dkimproxy";
+  version = "1.4.1";
+
+  src = fetchurl {
+    url = "mirror://sourceforge/dkimproxy/${pname}-${version}.tar.gz";
+    sha256 = "1gc5c7lg2qrlck7b0lvjfqr824ch6jkrzkpsn0gjvlzg7hfmld75";
+  };
+
+  # Idea taken from pkgs/development/perl-modules/generic/builder.sh
+  preFixup = ''
+    perlFlags=
+    for i in $(IFS=:; echo $PERL5LIB); do
+      perlFlags="$perlFlags -I$i"
+    done
+    for f in $(ls $out/bin); do
+      sed -i $out/bin/$f -e "s|#\!\(.*/perl.*\)$|#\! \1 $perlFlags|"
+    done
+  '';
+
+  buildInputs = [ perlPackages.perl ];
+  propagatedBuildInputs = with perlPackages; [ Error MailDKIM MIMETools NetServer ];
+
+  meta = with lib; {
+    description = "SMTP-proxy that signs and/or verifies emails";
+    homepage = "http://dkimproxy.sourceforge.net/";
+    license = licenses.gpl2Plus;
+    maintainers = [ maintainers.ekleog ];
+    platforms = platforms.all;
+  };
+}