drivers: uart_liteuart: fix usage of DT_ defines
drivers: uart_liteuart: fix usage of DT_ defines

This commit switches from using device tree automatically
generated address-based defines to the instance id-based ones.

Without this change it is not be possible to re-use the driver
on boards where the device is located at different location
than 0xe0001800.

Signed-off-by: Mateusz Holenko <1a79f421828d0048009fccfd7504972981cac7dd@antmicro.com>

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