modules: hal_gigadevice: make compile definitions global
modules: hal_gigadevice: make compile definitions global

GD32F4XX requires access to SoC definitions (e.g. GD32F450) when
including library header files, so expose them at Zephyr level.

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

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