CONFIG_ARCH_OXNAS is not available for thedefaultarchitecture x86.
Result is shown for architecture arm
Oxford Semiconductor OXNAS Family SoCs
configname: CONFIG_ARCH_OXNAS
Linux Kernel Configuration
└─>Oxford Semiconductor OXNAS Family SoCs
In linux kernel since version 3.10 (release Date: 2013-06-30)
Support for OxNas SoC family developed by Oxford Semiconductor.