default or selected kernelversion does not have config value CONFIG_BACKLIGHT_ADX.
Result is shown for kernelversion 6.2.5

Avionic Design Xanthos Backlight Driver

modulename: adx_bl.ko

configname: CONFIG_BACKLIGHT_ADX

Linux Kernel Configuration
└─>Device Drivers
└─>Graphics support
└─>Backlight & LCD device support
└─>Avionic Design Xanthos Backlight Driver
In linux kernel since version 2.6.32 (release Date: 2009-12-02)  
Say Y to enable the backlight driver on Avionic Design Xanthos-based
boards.

source code:
drivers/video/backlight//adx_bl.c