drivers: sock_flash_nrf: Report errors to log
drivers: sock_flash_nrf: Report errors to log

Report errors using logging subsystem so it is easier to
see the error location while debugging code.

Signed-off-by: Ievgenii Meshcheriakov <df2064527cff29064d40b3c65720cad00a28b85e@nordicsemi.no>

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