[nrf fromlist] samples: boards: nordic: system_off: Add GRTC wakeup#2074

rlubos merged 1 commit intonrfconnect:mainnrfconnect/sdk-zephyr:mainfrom

nordic-babu:sysoff-grtcnordic-babu/sdk-zephyr:sysoff-grtcCopy head branch name to clipboard