default or selected kernelversion does not have config value CONFIG_LUSTRE_DEBUG_EXPENSIVE_CHECK.
Result is shown for kernelversion 6.7-rc3

Enable Lustre DEBUG checks


Linux Kernel Configuration
└─>Device Drivers
└─>Staging drivers
└─>Enable Lustre DEBUG checks
In linux kernel since version 3.11 (release Date: 2013-09-02)  
This option is mainly for debug purpose. It enables Lustre code to do
expensive checks that may have a performance impact.

Use with caution. If unsure, say N.