default or selected kernelversion does not have config value CONFIG_KVM_DEBUG_FS.
Result is shown for kernelversion 6.7.7

Enable debug information for KVM Guests in debugfs

configname: CONFIG_KVM_DEBUG_FS

Linux Kernel Configuration
└─>Processor type and features
└─>Linux guest support
└─>Enable debug information for KVM Guests in debugfs
In linux kernel since version 3.12 (release Date: 2013-11-03)  
This option enables collection of various statistics for KVM guest.
Statistics are displayed in debugfs filesystem. Enabling this option
may incur significant overhead.