[usbdev] Update D2S checklist items
[usbdev] Update D2S checklist items

USBDEV does not have any notable countermeasures except for the
bus-integrity error, hence we can mark them as done / N/A as has been
done for other non-security critical peripherals.

Signed-off-by: Michael Schaffner <a005a2d3342a687ea2d05360c953107acbe83e08@opentitan.org>

lowRISC/opentitan,lowRISC/opentitan,lowRISC/opentitan,lowRISC/opentitan,lowRISC/opentitan,lowRISC/opentitan