rtc: ds3232: use rtc_lock/rtc_unlock

Avoid accessing directly rtc->ops_lock and use the RTC core helpers.
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
Link: https://lore.kernel.org/r/20210119220653.677750-6-alexandre.belloni@bootlin.com

drivers/rtc/rtc-ds3232.c

@@ -406,11 +406,10 @@ static irqreturn_t ds3232_irq(int irq, void *dev_id)
 {
 	struct device *dev = dev_id;
 	struct ds3232 *ds3232 = dev_get_drvdata(dev);
-	struct mutex *lock = &ds3232->rtc->ops_lock;
 	int ret;
 	int stat, control;
 
-	mutex_lock(lock);
+	rtc_lock(ds3232->rtc);
 
 	ret = regmap_read(ds3232->regmap, DS3232_REG_SR, &stat);
 	if (ret)
@@ -448,7 +447,7 @@ static irqreturn_t ds3232_irq(int irq, void *dev_id)
 	}
 
 unlock:
-	mutex_unlock(lock);
+	rtc_unlock(ds3232->rtc);
 
 	return IRQ_HANDLED;
 }