drm/xe: Remove ci-only GuC FW definitions

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.

Signed-off-by: Daniele Ceraolo Spurio <daniele.ceraolospurio@intel.com>
Cc: Rodrigo Vivi <rodrigo.vivi@intel.com>
Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Signed-off-by: Rodrigo Vivi <rodrigo.vivi@intel.com>