default or selected kernelversion does not have config value CONFIG_SIRFSOC_WATCHDOG.
Result is shown for kernelversion 6.9.9

SiRFSOC watchdog

modulename: sirfsoc_wdt.ko

configname: CONFIG_SIRFSOC_WATCHDOG

Linux Kernel Configuration
└─>Device Drivers
└─>Watchdog Timer Support
└─>SiRFSOC watchdog
In linux kernel since version 3.13 (release Date: 2014-01-19)  
Support for CSR SiRFprimaII and SiRFatlasVI watchdog. When
the watchdog triggers the system will be reset.

source code:

depends
CONFIG_HAS_IOMEM
CONFIG_WATCHDOG
CONFIG_ARCH_SIRF or CONFIG_COMPILE_TEST