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

Support Versatile/PB platform

modulename: versatile_pb.ko

configname: CONFIG_ARCH_VERSATILE_PB

Linux Kernel Configuration
└─>Versatile platform type
└─>Support Versatile/PB platform
In linux kernel since version 2.6.12  
Include support for the ARM(R) Versatile/PB platform.

source code:
arch/arm/mach-versatile/versatile_pb.c

is selected by
CONFIG_CPU_ARM926T