CONFIG_CPU_LOONGSON1B is not available for thedefaultarchitecture x86.
Result is shown for architecture mips

Loongson 1B

configname: CONFIG_CPU_LOONGSON1B

CPU type
└─>Loongson 1B
In linux kernel since version 3.1 (release Date: 2011-10-24)  
The Loongson 1B is a 32-bit SoC, which implements the MIPS32
Release 1 instruction set and part of the MIPS32 Release 2
instruction set.