nixos/qt5ct: remove enable option and suggests qt5.platformTheme

This module should be removed after a nixos release cycle

nixos/modules/programs/qt5ct.nix

···
-{ config, lib, pkgs, ... }:
+{ lib, ... }:
 
 with lib;
 
 {
-  meta.maintainers = [ maintainers.romildo ];
-
-  ###### interface
-  options = {
-    programs.qt5ct = {
-      enable = mkOption {
-        default = false;
-        type = types.bool;
-        description = ''
-          Whether to enable the Qt5 Configuration Tool (qt5ct), a
-          program that allows users to configure Qt5 settings (theme,
-          font, icons, etc.) under desktop environments or window
-          manager without Qt integration.
-
-          Official home page: <link xlink:href="https://sourceforge.net/projects/qt5ct/">https://sourceforge.net/projects/qt5ct/</link>
-        '';
-      };
-    };
-  };
-
-  ###### implementation
-  config = mkIf config.programs.qt5ct.enable {
-    environment.variables.QT_QPA_PLATFORMTHEME = "qt5ct";
-    environment.systemPackages = with pkgs; [ libsForQt5.qt5ct ];
-  };
+  imports = [
+    (mkRemovedOptionModule [ "programs" "qt5ct" "enable" ] "Use qt5.platformTheme = \"qt5ct\" instead.")
+  ];
 }