default or selected kernelversion does not have config value CONFIG_UBIFS_FS_DEBUG_CHKS.
Result is shown for kernelversion 5.4.69

Enable extra checks


Linux Kernel Configuration
└─>File systems
└─>Miscellaneous filesystems
└─>Enable extra checks
In linux kernel since version 2.6.27 (release Date: 2008-10-09)  
If extra checks are enabled UBIFS will check the consistency of its
internal data structures during operation. However, UBIFS performance
is dramatically slower when this option is selected especially if the
file system is large.