task_ssm_done cleared task_ssm before calling maybe_cancel, so
identify_cancel_ssm_done couldn't tell whether the identify already
completed or was cancelled. Use fpi_device_action_is_cancelled()
and skip the duplicate identify_complete call in IDENTIFY_COMPLETE
state when cancelled, letting the cancel flow handle completion.
Cancelling an operation does allow the driver to do perform async ops
at the moment, but rather we are supposed to just send the the cancel
commands while another action may running.
So we should handle this as part of the SSM final stage, if cancellation
happened.
Add IDENTIFY_SEND_CANCEL_RESULT state to send cancel command
after identify/verify completes, triggering firmware template update.
Implement cancel() callback for enroll and identify/verify cancellation.
Updated umockdev test data to cover the new flow.
