nsd module: make use of NSDs configFile option

Signed-off-by: Christoph Hrdinka <c.github@hrdinka.at>

nixos/modules/services/networking/nsd.nix

@@ -11,6 +11,8 @@ let
 
   # build nsd with the options needed for the given config
   nsdPkg = pkgs.nsd.override {
+    configFile = "${configFile}/nsd.conf";
+
     bind8Stats = cfg.bind8Stats;
     ipv6 = cfg.ipv6;
     ratelimit = cfg.ratelimit.enable;
@@ -788,6 +790,8 @@ in
 
   config = mkIf cfg.enable {
 
+    environment.systemPackages = [ nsdPkg ];
+
     users.extraGroups = singleton {
       name = username;
       gid = config.ids.gids.nsd;
@@ -845,4 +849,6 @@ in
     };
 
   };
+
+  meta.maintainers = with lib.maintainers; [ hrdinka ];
 }