MAINTAINERS: Add simonguinot as the LED collaborator
MAINTAINERS: Add simonguinot as the LED collaborator

Simon has been helping out with the reviews of the LED PRs. So let's add
him as a collaborator to help PRs move forward.

Signed-off-by: Manivannan Sadhasivam <7cdffa2a61f6c51ff0ae24b4793b8c7f31d1b1b0@linaro.org>

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