CONFIG_CAVIUM_OCTEON_2ND_KERNEL is not available for thedefaultarchitecture x86.
Result is shown for architecture mips
default or selected kernelversion does not have config value CONFIG_CAVIUM_OCTEON_2ND_KERNEL.
Result is shown for kernelversion 6.5.1

Build the kernel to be used as a 2nd kernel on the same chip

configname: CONFIG_CAVIUM_OCTEON_2ND_KERNEL

Linux Kernel Configuration
└─>Build the kernel to be used as a 2nd kernel on the same chip
In linux kernel since version 2.6.29 (release Date: 2009-03-23)  
This option configures this kernel to be linked at a different
address and use the 2nd uart for output. This allows a kernel built
with this option to be run at the same time as one built without this
option.