Add nrfconnect_firmware_utils.py (#5666)
Add nrfconnect_firmware_utils.py (#5666)

* Add nrfconnect_firmware_utils.py

#### Problem

The former `nrf5_firmware_utils.py` was not replaced in the transition
from the old SDK to nRF Connect.

#### Summary of Changes

This is based on `nrf5_firmware_utils.py` (removed at e931c964)
with small changes to `nrfjprog` arguments, to match the actions
of `west flash`.

As with other platforms, an image can be flashed using

    ${PLATFORM}_firmware_utils.py --application ${IMAGE}

(Since the nRF examples are not built through GN, there is currently
no `${IMAGE}.flash.py`.)

* review

* update copyright to kick the restyler
nestlabs/connectedhomeip,project-chip/connectedhomeip,project-chip/connectedhomeip,nestlabs/connectedhomeip,nestlabs/connectedhomeip,project-chip/connectedhomeip,project-chip/connectedhomeip,nestlabs/connectedhomeip,nestlabs/connectedhomeip,project-chip/connectedhomeip,project-chip/connectedhomeip,nestlabs/connectedhomeip,nestlabs/connectedhomeip