nixos/{corefreq, auditd}: fix mkEnableOption description (#544621)

nixos/modules/programs/corefreq.nix

@@ -12,7 +12,7 @@ in
 {
   options = {
     programs.corefreq = {
-      enable = lib.mkEnableOption "Whether to enable the corefreq daemon and kernel module";
+      enable = lib.mkEnableOption "the corefreq daemon and kernel module";
 
       package = lib.mkOption {
         type = lib.types.package;

nixos/modules/security/auditd.nix

@@ -18,7 +18,7 @@ let
 
   pluginOptions = lib.types.submodule {
     options = {
-      active = lib.mkEnableOption "Whether to enable this plugin";
+      active = lib.mkEnableOption "this plugin";
       direction = lib.mkOption {
         type = lib.types.enum [
           "in"