drivers: gpio_mcux: clean up interrupt code
drivers: gpio_mcux: clean up interrupt code

Remove redundant interrupt code from gpio_mcux_configure, move the rest
to gpio_mcux_pin_interrupt_configure.

Signed-off-by: Piotr Mienkowski <be7d9ab625d3cb5e3a4a3202f3529b954dba084c@gmail.com>

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