nixos/avahi: move nss database configuration into avahi module

nixos/modules/services/networking/avahi-daemon.nix

@@ -238,6 +238,10 @@ in
     users.groups.avahi = {};
 
     system.nssModules = optional cfg.nssmdns pkgs.nssmdns;
+    system.nssDatabases.hosts = optionals cfg.nssmdns (mkMerge [
+      [ "mdns_minimal [NOTFOUND=return]" ]
+      (mkOrder 1501 [ "mdns" ]) # 1501 to ensure it's after dns
+    ]);
 
     environment.systemPackages = [ pkgs.avahi ];