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

RAS features for bare metal Cell BE

modulename: ras.ko

configname: CONFIG_CBE_RAS

Linux Kernel Configuration
└─>Cell Broadband Engine options
└─>RAS features for bare metal Cell BE
In linux kernel since version 2.6.18 (release Date: 2006-09-19)  
source code:
arch/powerpc/platforms/cell/ras.c