remove dead code (run deadnix)

doc/extract-options.nix

@@ -1,6 +1,5 @@
 { eval, lib, pkgs }:
 let
-  inherit (lib) types;
   conf = eval.config;
   rootDir = builtins.toPath ./..;
   stripAnyPrefixes = lib.flip (lib.fold lib.removePrefix)

doc/hardware.nix

@@ -9,14 +9,6 @@ let
         d' = {
           description = "${n}\n${substring 0 (stringLength n) "********************************"}\n";
         } // d;
-        installer =
-          if d ? description && d ? installer
-          then ''
-
-            The default installation route for this device is
-            :ref:`system-outputs-${d.installer}`
-          ''
-          else "";
     in d'.description)
     devices;
 in