rtc: asm9260: 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/20210119220653.677750-2-alexandre.belloni@bootlin.com

drivers/rtc/rtc-asm9260.c

@@ -116,15 +116,15 @@ static irqreturn_t asm9260_rtc_irq(int irq, void *dev_id)
 	u32 isr;
 	unsigned long events = 0;
 
-	mutex_lock(&priv->rtc->ops_lock);
+	rtc_lock(priv->rtc);
 	isr = ioread32(priv->iobase + HW_CIIR);
 	if (!isr) {
-		mutex_unlock(&priv->rtc->ops_lock);
+		rtc_unlock(priv->rtc);
 		return IRQ_NONE;
 	}
 
 	iowrite32(0, priv->iobase + HW_CIIR);
-	mutex_unlock(&priv->rtc->ops_lock);
+	rtc_unlock(priv->rtc);
 
 	events |= RTC_AF | RTC_IRQF;