drivers: interrupt_controller: gd32_exti: enable gd32vf103
drivers: interrupt_controller: gd32_exti: enable gd32vf103

The device implemented by this driver is also available on GD32 RISC-V
MCUs.

Signed-off-by: Gerard Marull-Paretas <76c1da08be458687d0066397d08e4f7ea9894377@teslabs.com>

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