default or selected kernelversion does not have config value CONFIG_MV64X60_WDT.
Result is shown for kernelversion 6.9.9

MV64X60 (Marvell Discovery) Watchdog Timer

modulename: mv64x60_wdt.ko

configname: CONFIG_MV64X60_WDT

Linux Kernel Configuration
└─>Device Drivers
└─>Watchdog Timer Support
└─>MV64X60 (Marvell Discovery) Watchdog Timer
In linux kernel since version 2.6.20 (release Date: 2007-02-04)  
source code:
drivers/watchdog/mv64x60_wdt.c
depends
CONFIG_WATCHDOG
CONFIG_COMPILE_TEST or CONFIG_MV64X60