Reference build using 'nrf52840' gives a non-responsive dongle while 'ncs' works

[EskoDijk]

When doing a reference build like below:

REFERENCE_PLATFORM=nrf52840 REFERENCE_RELEASE_TYPE=1.4 ./script/make-reference-release.bash

the resulting dongle firmware for NRF52840 can be programmed into the dongle, but doesn't work.

• no serial port shows up for the CLI FTD build when inserting the dongle;
• dongle cannot be enumerated using lsusb (does not display at all)

When replacing he platform with ncs , the CLI FTD dongle does work with the same NRF 52840 hardware. So this could be an issue in this repo, as suggested by @maciejbaczmanski .