So it worked?
I'm not too interested in adding the txt files to our main distro as the driver-named file is not enough and I'd be concerned that the brcmfmac-sdio named files will conflict with other brcmfmac devices. I'd ask you to test a current milhouse release as well, as those will have newer kernels with newer versions of the brcmfmac driver. Plan C .. you need to learn how to self-compile an image to repeat the process I did (which is trivial).