Dear Nordic Engineers
I use the NCS V1.9.1.I would like to building the openthread\coprocessor project on the nrf52840_dongle.I read this page:https://developer.nordicsemi.com/nRF_Connect_SDK/doc/1.9.1/nrf/samples/openthread/coprocessor/README.html.
The coprocessor sample support the nrf 52840 dongle.

But an error occurred during the construction of the project.

I try to create a new .overlay file.But look like it's useless.

Please help me,how to building the openthread\coprocessor project on the nrf52840_dongle?
Best regards.
