drm/xe: remove stale runtime_pm member

This has become unused and unnecessary. Remove.

Reviewed-by: Rodrigo Vivi <rodrigo.vivi@intel.com>
Link: https://patch.msgid.link/20251112185547.172113-1-jani.nikula@intel.com
Signed-off-by: Jani Nikula <jani.nikula@intel.com>

Author: jnikula

drivers/gpu/drm/xe/xe_device_types.h

@@ -645,9 +645,6 @@ struct xe_device {
 	 */
 	u32 edram_size_mb;
 
-	/* To shut up runtime pm macros.. */
-	struct xe_runtime_pm {} runtime_pm;
-
 	struct intel_uncore {
 		spinlock_t lock;
 	} uncore;