CONFIG_MACH_U8500_MOP is not available for thedefaultarchitecture x86.
Result is shown for architecture arm
default or selected kernelversion does not have config value CONFIG_MACH_U8500_MOP.
Result is shown for kernelversion 5.4.69

U8500 Development platform

modulename: board-mop500.ko

configname: CONFIG_MACH_U8500_MOP

Ux500 target platform
└─>U8500 Development platform
In linux kernel since version 2.6.33 (release Date: 2010-02-24)  
Include support for the mop500 development platform.

source code: