default or selected kernelversion does not have config value CONFIG_B43_BCMA_EXTRA.
Result is shown for kernelversion 6.2.5

Hardware support that overlaps with the brcmsmac driver

configname: CONFIG_B43_BCMA_EXTRA

Linux Kernel Configuration
└─>Device Drivers
└─>Network device support
└─>Wireless LAN
└─>Hardware support that overlaps with the brcmsmac driver
In linux kernel since version 3.1 (release Date: 2011-10-24)