w0: nixos: disable virtualbox
w0: nixos: disable virtualbox

We've never used it inside the VM. Plus, the Mac guest's CPU does not
support hardware acceleration for virtualization, so it appears that we
cannot use 64-bit systems inside here anyway.

The pkgs.lib.mkForce is from
https://nixos.org/nixos/manual/#sec-modularity.

listx/syscfg,listx/syscfg,listx/syscfg,listx/syscfg,listx/syscfg