drivers: gpio_pca95xx: no longer support config by port
drivers: gpio_pca95xx: no longer support config by port

Remove support for GPIO_ACCESS_BY_PORT in the config function
as configuration by port is going away.

Signed-off-by: Daniel Leung <d94e04d205b5962d7873a139ef298b03c1717f72@intel.com>

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