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

Bootloader kernel arguments if available

configname: CONFIG_MIPS_CMDLINE_FROM_BOOTLOADER

Kernel command line type
└─>Bootloader kernel arguments if available
In linux kernel since version 4.1 (release Date: 2015-06-21)