CONFIG_MACH_REALVIEW_PB1176 is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

Support RealView/PB1176 platform

modulename: realview_pb1176.ko

configname: CONFIG_MACH_REALVIEW_PB1176

Linux Kernel Configuration
└─>RealView platform type
└─>Support RealView/PB1176 platform
In linux kernel since version 2.6.26 (release Date: 2008-07-13)  
Include support for the ARM(R) RealView ARM1176 Platform Baseboard.

source code: