modules: Change serialized radio init priority
modules: Change serialized radio init priority

This commit changes serialized radio initialization
priority. This fixes race condition where serialization
backend would boot earlier than the radio driver itself.

Signed-off-by: Pawel Kwiek <3b496674e19403d7bda2d0850fd5a48a199a4bfd@nordicsemi.no>

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