CONFIG_NVHE_EL2_DEBUG is not available for thedefaultarchitecture x86.
Result is shown for architecture arm64

Debug mode for non-VHE EL2 object

configname: CONFIG_NVHE_EL2_DEBUG

Linux Kernel Configuration
└─>Virtualization
└─>Kernel-based Virtual Machine (KVM) support
└─>Debug mode for non-VHE EL2 object
In linux kernel since version 5.2 (release Date: 2019-07-07)  
Say Y here to enable the debug mode for the non-VHE KVM EL2 object.
Failure reports will BUG() in the hypervisor. This is intended for
local EL2 hypervisor development.

If unsure, say N.