CONFIG_PPC_RTAS_DAEMON is not available for thedefaultarchitecture x86.
Result is shown for architecture powerpc

CONFIG_PPC_RTAS_DAEMON (not configurable)

modulename: rtasd.ko

configname: CONFIG_PPC_RTAS_DAEMON

Linux Kernel Configuration
└─>Platform support
└─>PPC_RTAS_DAEMON
In linux kernel since version 2.6.33 (release Date: 2010-02-24)  
source code:
arch/powerpc/kernel/rtasd.c
depends
CONFIG_PPC_RTAS