MAINTAINERS: add cameled as gd32 platform collaborator
MAINTAINERS: add cameled as gd32 platform collaborator

Add cameled as gd32 platform collaborator.

Signed-off-by: HaiLong Yang <c5b53c3148d79a31d58d6febcc7e03b084440d0f@brainco.cn>

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