hardware/u2f: remove module

udev gained native support to handle FIDO security tokens, so we don't
need a module which only added the now obsolete udev rules.

Fixes: https://github.com/NixOS/nixpkgs/issues/76482

nixos/modules/module-list.nix

@@ -362,7 +362,6 @@
   ./services/hardware/throttled.nix
   ./services/hardware/trezord.nix
   ./services/hardware/triggerhappy.nix
-  ./services/hardware/u2f.nix
   ./services/hardware/udev.nix
   ./services/hardware/udisks2.nix
   ./services/hardware/upower.nix