CONFIG_83xx_WDT is not available for the default architecture x86.
Result is shown for architecture um
default or selected kernelversion does not have config value CONFIG_83xx_WDT.
Result is shown for kernelversion

MPC83xx Watchdog Timer

modulename: mpc83xx_wdt.ko
configname: CONFIG_83xx_WDT

Linux Kernel Configuration
└─> Device Drivers
└─> Watchdog Timer Support
└─> MPC83xx Watchdog Timer

source code: