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

CONFIG_PPC_CELL_NATIVE (not configurable)

modulename: iommu.ko

and/or

smp.ko

configname: CONFIG_PPC_CELL_NATIVE

Linux Kernel Configuration
└─>PPC_CELL_NATIVE
In linux kernel since version 2.6.18 (release Date: 2006-09-19)  
source code:
/arch/powerpc/platforms/cell/