Do you have package sof-firmware installed? I do seem to have it even without relevant hardware:
rene@p55m:~$ pacman -Ss sof-firmware
extra/sof-firmware 2.2.2-1 [installed]
Sound Open Firmware
so maybe you also already do but if not then I expect that installing that and rebooting might work. I.e., Comet Lake PCH-LP cAVS sound card not detected after latest update