CONFIG_ARCH_REALTEK is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

Realtek SoCs

configname: CONFIG_ARCH_REALTEK

Linux Kernel Configuration
└─>Realtek SoCs
In linux kernel since version 3.10 (release Date: 2013-06-30)  
This enables support for the Realtek RTD1195 SoC family.



is selected by
CONFIG_RTD119X_WATCHDOG