drivers: gpio_ite_it8xxx2: fix use of uninitialized variable
drivers: gpio_ite_it8xxx2: fix use of uninitialized variable

Retain the assumption that the loop will assign a pointer, but
initialize it pointer first to eliminate build warnings.

Signed-off-by: Peter Bigot <a4112a160b558d5427af084318038e19a95979ee@nordicsemi.no>

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