FTR, it seems that kernel-firmware-brcm's license: /usr/share/licenses/kernel-firmware-brcm/LICENCE.broadcom_bcm43xx (which we distribute) is the same as for brcmfmac43456-sdio.pine64,pinebook-pro.bin: https://github.com/bsdkurt/brcm-supplemental/blob/master/LICENSE in https://github.com/bsdkurt/brcm-supplemental