drivers: interrupt_controller: 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 timer and uart devices are located at different
locations than 0xe0002800 and 0xe0001800 respectively.

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