default or selected kernelversion does not have config value CONFIG_BATMAN_DEBUG.
Result is shown for kernelversion 5.4.194

B.A.T.M.A.N. debugging

configname: CONFIG_BATMAN_DEBUG

Linux Kernel Configuration
└─>Device Drivers
└─>Staging drivers
└─>B.A.T.M.A.N. debugging
In linux kernel since version 2.6.33 (release Date: 2010-02-24)  
This is an option for use by developers; most people should
say N here. This enables compilation of support for
outputting debugging information to the kernel log. The
output is controlled via the module parameter debug.