default or selected kernelversion does not have config value CONFIG_WDT_RM9K_GPI.
Result is shown for kernelversion 5.4.159

RM9000/GPI hardware watchdog

modulename: rm9k_wdt.ko

configname: CONFIG_WDT_RM9K_GPI

Linux Kernel Configuration
└─>Device Drivers
└─>Watchdog Timer Support
└─>RM9000/GPI hardware watchdog
In linux kernel since version 2.6.20 (release Date: 2007-02-04)  
Watchdog implementation using the GPI hardware found on
PMC-Sierra RM9xxx CPUs.

To compile this driver as a module, choose M here: the
module will be called rm9k_wdt.

source code: