In Arch Linux
mkinitcpio -p linux
shows
Possibly missing firmware for module: aic94xx
Possibly missing firmware for module: wd719x
git clone https://aur.archlinux.org/aic94xx-firmware.git
cd aic94xx-firmware
makepkg -sri
git clone https://aur.archlinux.org/wd719x-firmware.git
cd wd719x-firmware
makepkg -sri
and then mkinitcpio -p linux
again.
We've already discussed why this thread exists. Thousands of pieces of firmware exist. You could warn about them all, but that would make the warning useless, and it might as well be removed. So the question is: why does it warn about these 3? What if pacman warned you about random programs you don't have installed every time you used it?
Warnings are supposed to alert of possible errors, and ignoring them regularly leads to issues. If people want to keep the warning, I'd suggest stating in the warning what hardware the firmware is for so you don't have to scrape the internet to figure out if each one applies to you. But the warning seems irrelevant to me.