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

iSeries Virtual I/O CD support

modulename: viocd.ko

configname: CONFIG_VIOCD

Linux Kernel Configuration
└─>iSeries device drivers
└─>iSeries Virtual I/O CD support
In linux kernel since version 2.6.15 (release Date: 2006-01-02)  
If you are running Linux on an IBM iSeries system and you want to
read a CD drive owned by OS/400, say Y here.

source code: