drm/xe/vf: Mark supported firmwares as preloaded

On current platforms supported firmwares, like GuC and HuC, must
be loaded by the PF driver.  Mark those firmwares as 'preloaded'
so we will skip fetching and loading them on the VF drivers but
still correctly report them as 'running'.

Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Reviewed-by: Piotr Piórkowski <piotr.piorkowski@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240404173814.715-1-michal.wajdeczko@intel.com