kernelconfig_penguin
default or selected kernelversion does not have config value CONFIG_ARM_BRCMSTB_AVS_CPUFREQ_DEBUG.
Result is shown for kernelversion 5.9.8

Broadcom STB AVS CPUfreq driver sysfs debug capability

configname: CONFIG_ARM_BRCMSTB_AVS_CPUFREQ_DEBUG

Linux Kernel Configuration
└─> Broadcom STB AVS CPUfreq driver sysfs debug capability

Enabling this option turns on debug support via sysfs under
/sys/kernel/debug/brcmstb-avs-cpufreq. It is possible to read all and
write some AVS mailbox registers through sysfs entries.

If in doubt, say N.