drm/xe/pf: Expose PF service details via debugfs

For debug purposes we might want to verify which registers values
PF is sharing with VFs and to view which VF/PF ABI versions were
negotiated by the VFs. Plug the 'print' functions already provided
by the PF service code into our debugfs.

Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Reviewed-by: Piotr Piórkowski <piotr.piorkowski@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240424171030.2177-1-michal.wajdeczko@intel.com