The firmware package provides /lib/firmware/brcm/brcmfmac43455-sdio.pine64,pinebook-pro.txt.xz -> brcmfmac43455-sdio.AW-CM256SM.txt.xz but the requested firmware is /lib/firmware/brcm/brcmfmac43456-sdio.pine64,pinebook-pro.bin 43455 vs 43456