CONFIG_SYS_HAS_CPU_CAVIUM_OCTEON is not available for thedefaultarchitecture x86.
Result is shown for architecture mips

CONFIG_SYS_HAS_CPU_CAVIUM_OCTEON (not configurable)

configname: CONFIG_SYS_HAS_CPU_CAVIUM_OCTEON

Linux Kernel Configuration
└─>CPU selection
└─>SYS_HAS_CPU_CAVIUM_OCTEON
In linux kernel since version 2.6.29 (release Date: 2009-03-23)  
is selected by
CONFIG_CPU_CAVIUM_OCTEON