CONFIG_PPC_970_NAP is not available for thedefaultarchitecture x86.
Result is shown for architecture powerpc

CONFIG_PPC_970_NAP (not configurable)

modulename: idle_power4.ko

configname: CONFIG_PPC_970_NAP

Linux/PowerPC Kernel Configuration
└─>Platform support
└─>PPC_970_NAP
In linux kernel since version 2.6.17 (release Date: 2006-06-17)  
source code:
arch/powerpc/kernel/