drm/xe: Restore IDLEDLY regiter on engine reset

drm/xe: Restore IDLEDLY regiter on engine reset

Wa_16023105232 programs the register IDLEDLY. The register is reset
whenever the engine is reset. Therefore it should be added to the GuC
save-restore register list for it to be restored after reset.

Fixes: 7c53ff050ba8 ("drm/xe: Apply Wa_16023105232")
Reviewed-by: Matt Roper <matthew.d.roper@intel.com>
Link: https://patch.msgid.link/20260522163531.1365540-2-balasubramani.vivekanandan@intel.com
Signed-off-by: Balasubramani Vivekanandan <balasubramani.vivekanandan@intel.com>