nixos: fixup device manager USB stuff

nixos-modules/hardware/usb.nix

@@ -1,15 +1,14 @@
 { config, pkgs, lib, ... }:
 
 with lib;
+let
+  mkEnableOption' = text: default:
+    lib.mkEnableOption text // {
+      inherit default;
+    };
+in {
 
-{
-  options.hardware.genode.usb = let
-    mkEnableOption' = text: default:
-      lib.mkEnableOption text // {
-        inherit default;
-      };
-  in {
-
+  options.hardware.genode.usb = {
     enable = lib.mkEnableOption "USB driver";
     storage.enable = lib.mkEnableOption "USB mass storage driver";
 
@@ -19,33 +18,13 @@ with lib;
     ohciSupport = mkEnableOption' "OHCI support" true;
     uhciSupport = mkEnableOption' "UHCI support" false;
     xhciSupport = mkEnableOption' "XHCI support" true;
-
   };
 
   config = let
     cfg = config.hardware.genode.usb;
-
     usbEris = lib.attrsets.mapAttrs (_: lib.getEris "bin") {
       inherit (pkgs.genodePackages) part_block usb_block_drv usb_drv;
     };
-
-    managerConfig = pkgs.writeText "usb_device_manager.dhall" ''
-      let Manager = ${pkgs.genodePackages.usb_device_manager.dhall}/package.dhall
-
-      in  Manager.toChildAttributes
-            Manager::{
-            , part_block.binary = "${usbEris.part_block.cap}"
-            , usb_block.binary = "${usbEris.usb_block_drv.cap}"
-            , usb_driver =
-              { binary = "${usbEris.usb_drv.cap}"
-              , bios_handoff = True
-              , ehci = True
-              , ohci = False
-              , uhci = False
-              , xhci = False
-              }
-            }
-    '';
   in {
 
     hardware.genode.usb.enable = lib.mkDefault cfg.storage.enable;