fix(nixos): Don't install audio/printing drivers on servers

modules/nixos/base/drivers/default.nix

@@ -1,4 +1,10 @@
-{pkgs, ...}: {
+{
+  pkgs,
+  config,
+  lib,
+  ...
+}: {
+  config = lib.mkIf (!config.marleyos.isServer) {
     security.rtkit.enable = true; # Used for pulseaudio.
 
     services = {
@@ -14,4 +20,5 @@
     };
 
     environment.systemPackages = [pkgs.pwvucontrol];
+  };
 }