kernel: Disable VirtualBox guest modules.

These break the modules from VirtualBox additions. Fixes issue https://github.com/NixOS/nixpkgs/issues/58127.

pkgs/os-specific/linux/kernel/common-config.nix

@@ -426,6 +426,12 @@ let
 
       VFIO_PCI_VGA = mkIf stdenv.is64bit yes;
 
+      # VirtualBox guest drivers in the kernel conflict with the ones in the
+      # official additions package and prevent the vboxsf module from loading,
+      # so disable them for now.
+      VBOXGUEST = option no;
+      DRM_VBOXVIDEO = option no;
+
     } // optionalAttrs (stdenv.isx86_64 || stdenv.isi686) ({
       XEN = option yes;