rtc: ds1305: use rtc_lock/rtc_unlock

Avoid accessing directly rtc->ops_lock and use the RTC core helpers.

Signed-off-by: Alexandre Belloni <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]

drivers/rtc/rtc-ds1305.c

···
 static void ds1305_work(struct work_struct *work)
 {
 	struct ds1305	*ds1305 = container_of(work, struct ds1305, work);
-	struct mutex	*lock = &ds1305->rtc->ops_lock;
 	struct spi_device *spi = ds1305->spi;
 	u8		buf[3];
 	int		status;
 
 	/* lock to protect ds1305->ctrl */
-	mutex_lock(lock);
+	rtc_lock(ds1305->rtc);
 
 	/* Disable the IRQ, and clear its status ... for now, we "know"
 	 * that if more than one alarm is active, they're in sync.
···
 	if (status < 0)
 		dev_dbg(&spi->dev, "clear irq --> %d\n", status);
 
-	mutex_unlock(lock);
+	rtc_unlock(ds1305->rtc);
 
 	if (!test_bit(FLAG_EXITING, &ds1305->flags))
 		enable_irq(spi->irq);