drm/xe/pf: Allow to view and replace VF GuC state over debugfs

drm/xe/pf: Allow to view and replace VF GuC state over debugfs

For feature enabling and testing purposes, allow to view saved VF
GuC state and to replace it, but only under strict debug config.

Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Cc: Michał Winiarski <michal.winiarski@intel.com>
Cc: Tomasz Lis <tomasz.lis@intel.com>
Reviewed-by: Michał Winiarski <michal.winiarski@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240912203817.1880-6-michal.wajdeczko@intel.com