CONFIG_MACH_LB88RC8480 is not available for thedefaultarchitecture x86.
Result is shown for architecture arm
default or selected kernelversion does not have config value CONFIG_MACH_LB88RC8480.
Result is shown for kernelversion 5.6.18

Marvell LB88RC8480 Development Board

modulename: lb88rc8480-setup.ko

configname: CONFIG_MACH_LB88RC8480

Linux Kernel Configuration
└─>Marvell Loki (88RC8480) Implementations
└─>Marvell LB88RC8480 Development Board
In linux kernel since version 2.6.27 (release Date: 2008-10-09)  
Say 'Y' here if you want your kernel to support the
Marvell LB88RC8480 Development Board.

source code:
/arch/arm/mach-loki/lb88rc8480-setup.c