From: Vitaly Kuznetsov on
gitlab.com
https://gitlab.com/cki-project/kernel-ark/-/merge_requests/1529#note_8065...
Hyper-V uses its own hyperv-keyboard ('CONFIG_HYPERV_KEYBOARD') driver but it
works through serio/atkbd (AFAIU). The suggestion to enable these options
comes from Microsoft when non-functioning keyboard issue was investigated.