hrtimer: Add missing ACCESS_PRIVATE() for hrtimer::function

The "function" field of struct hrtimer has been changed to private, but
two instances have not been converted to use ACCESS_PRIVATE().

Convert them to use ACCESS_PRIVATE().

Fixes: 04257da ("hrtimers: Make callback function pointer private")
Reported-by: kernel test robot <lkp@intel.com>
Signed-off-by: Nam Cao <namcao@linutronix.de>
Signed-off-by: Thomas Gleixner <tglx@linutronix.de>
Link: https://lore.kernel.org/all/20250408103854.1851093-1-namcao@linutronix.de
Closes: https://lore.kernel.org/oe-kbuild-all/202504071931.vOVl13tt-lkp@intel.com/
Closes: https://lore.kernel.org/oe-kbuild-all/202504072155.5UAZjYGU-lkp@intel.com/

include/linux/hrtimer.h

@@ -345,7 +345,7 @@ static inline void hrtimer_update_function(struct hrtimer *timer,
 	if (WARN_ON_ONCE(!function))
 		return;
 #endif
-	timer->function = function;
+	ACCESS_PRIVATE(timer, function) = function;
 }
 
 /* Forward a hrtimer so it expires after now: */

kernel/time/hrtimer.c

@@ -366,7 +366,7 @@ static const struct debug_obj_descr hrtimer_debug_descr;
 
 static void *hrtimer_debug_hint(void *addr)
 {
-	return ((struct hrtimer *) addr)->function;
+	return ACCESS_PRIVATE((struct hrtimer *)addr, function);
 }
 
 /*