drm/xe/vf: Use register values obtained from the PF

As part of the its initialization, the VF driver has already
obtained a list of the runtime (fuse) register values from the
PF driver. When VF driver is attempting to read register that is
inaccessible to the VF, use the values from this list instead.

Signed-off-by: Michal Wajdeczko <michal.wajdeczko@intel.com>
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patchwork.freedesktop.org/patch/msgid/20240523192240.844-2-michal.wajdeczko@intel.com