CONFIG_SOC_TI81XX is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

TI81XX support

modulename: ti81xx-restart.ko

and/or

clockdomains81xx_data.ko

and/or

omap_hwmod_81xx_data.ko

configname: CONFIG_SOC_TI81XX

Linux Kernel Configuration
└─>TI OMAP/AM/DM/DRA Family
└─>TI OMAP2/3/4 Specific Features
└─>TI81XX support
In linux kernel since version 3.1 (release Date: 2011-10-24)  
source code:
arch/arm/mach-omap2/ti81xx-restart.c