CONFIG_MIPS_MACHINE is not available for thedefaultarchitecture x86.
Result is shown for architecture mips

CONFIG_MIPS_MACHINE (not configurable)

modulename: mips_machine.ko

configname: CONFIG_MIPS_MACHINE

Linux Kernel Configuration
└─>MIPS_MACHINE
In linux kernel since version 2.6.38 (release Date: 2011-03-14)  
source code:
arch/mips/kernel/mips_machine.c