default or selected kernelversion does not have config value CONFIG_NUC900_WATCHDOG.
Result is shown for kernelversion 6.7-rc3

Nuvoton NUC900 watchdog

modulename: nuc900_wdt.ko

configname: CONFIG_NUC900_WATCHDOG

Linux Kernel Configuration
└─>Device Drivers
└─>Watchdog Timer Support
└─>Nuvoton NUC900 watchdog
In linux kernel since version 2.6.32 (release Date: 2009-12-02)  
Say Y here if to include support for the watchdog timer
for the Nuvoton NUC900 series SoCs.
To compile this driver as a module, choose M here: the
module will be called nuc900_wdt.

source code:
depends
CONFIG_WATCHDOG
CONFIG_ARCH_W90X900 or CONFIG_COMPILE_TEST