samples: mgmt: updatehub: Add OpenThread support
samples: mgmt: updatehub: Add OpenThread support

Add OpenThread overlays.  This allows users to evaluate UpdateHub using
Thread Network.

Signed-off-by: Gerson Fernando Budke <de7eb9f159f7e30f8dcdecee89db6e1a285bf5b2@ossystems.com.br>

finikorg/zephyr,finikorg/zephyr,nashif/zephyr,Vudentz/zephyr,Vudentz/zephyr,galak/zephyr,finikorg/zephyr,galak/zephyr,finikorg/zephyr,galak/zephyr,zephyrproject-rtos/zephyr,nashif/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr,Vudentz/zephyr,zephyrproject-rtos/zephyr,zephyrproject-rtos/zephyr,finikorg/zephyr,nashif/zephyr,nashif/zephyr,galak/zephyr,Vudentz/zephyr,Vudentz/zephyr,nashif/zephyr,galak/zephyr,Vudentz/zephyr