CONFIG_ARCH_NPCM7XX is not available for thedefaultarchitecture x86.
Result is shown for architecture arm

Support for NPCM7xx BMC (Poleg)

modulename: npcm7xx.ko

and/or

clk-npcm7xx.ko

configname: CONFIG_ARCH_NPCM7XX

Linux Kernel Configuration
└─>Nuvoton NPCM Architecture
└─>Support for NPCM7xx BMC (Poleg)
In linux kernel since version 3.10 (release Date: 2013-06-30)  
General support for NPCM7xx BMC (Poleg).

Nuvoton NPCM7xx BMC based on the Cortex A9.

source code: