PM: runtime: Mark last busy stamp in pm_runtime_autosuspend()

Set device's last busy timestamp to current time in
pm_runtime_autosuspend().

Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Reviewed-by: Laurent Pinchart <laurent.pinchart@ideasonboard.com>
Link: https://patch.msgid.link/20250616061212.2286741-5-sakari.ailus@linux.intel.com


Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>