As part of the FW definitions, we declare each blob as required via the
MODULE_FIRMWARE() macro. This causes the initramfs update (or equivalent
process) to look for the blobs on disk when the kernel is installed;
therefore, we need to make sure that all FWs we define are available in
linux-firmware.
We currently don't plan to push the PVC blob to linux-firmware, while the
LNL one will only be pushed once we have machines in CI to test it, so we
need to remove them from the list for now.