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

iSeries Virtual Console Support

modulename: viocons.ko

configname: CONFIG_VIOCONS

Linux Kernel Configuration
└─>iSeries device drivers
└─>iSeries Virtual Console Support
In linux kernel since version 2.6.15 (release Date: 2006-01-02)  
source code:
drivers/char/viocons.c

is selected by
CONFIG_HVC_ISERIES