rmilter: remove unused files

The merge 98640fd48212f8e6552517f667bba1901f5936d4 was done incorrectly.

pkgs/servers/mail/rmilter/default.nix

@@ -1,33 +0,0 @@
-{ stdenv, fetchFromGitHub, cmake, bison, flex, pkgconfig, openssl, pcre
-, libmilter, opendkim, libmemcached, glib }:
-
-let patchedLibmilter = stdenv.lib.overrideDerivation  libmilter (_ : {
-    patches = libmilter.patches ++ [ ./fd-passing-libmilter.patch ];
-});
-in
-
-stdenv.mkDerivation rec {
-  pname = "rmilter";
-  version = "1.10.0";
-
-  src = fetchFromGitHub {
-    owner = "vstakhov";
-    repo = "rmilter";
-    rev = version;
-    sha256 = "1gbp6jah88l6xqgflim01ycyp63l733bgir65fxnnrmifj1qzymh";
-  };
-
-  nativeBuildInputs = [ bison cmake flex pkgconfig ];
-  buildInputs = [ libmemcached patchedLibmilter openssl pcre opendkim glib ];
-
-  meta = with stdenv.lib; {
-    homepage = https://github.com/vstakhov/rmilter;
-    license = licenses.asl20;
-    description = ''
-      Daemon to integrate rspamd and milter compatible MTA, for example
-      postfix or sendmail
-    '';
-    maintainers = with maintainers; [ avnik fpletz ];
-    platforms = with platforms; linux;
-  };
-}