CONFIG_DMA_NONCOHERENT is not available for thedefaultarchitecture x86.
Result is shown for architecture sh

CONFIG_DMA_NONCOHERENT (not configurable)

configname: CONFIG_DMA_NONCOHERENT

Linux Kernel Configuration
└─>DMA_NONCOHERENT
In linux kernel since version 2.6.12  
is depended by
CONFIG_CPU_BMIPS