rtc: mc13xxx: fix style issue

Use unsigned int instead of unsigned.

Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
diff --git a/drivers/rtc/rtc-mc13xxx.c b/drivers/rtc/rtc-mc13xxx.c
index 475def1..afce2c0 100644
--- a/drivers/rtc/rtc-mc13xxx.c
+++ b/drivers/rtc/rtc-mc13xxx.c
@@ -155,7 +155,7 @@ static int mc13xxx_rtc_set_time(struct device *dev, struct rtc_time *tm)
 static int mc13xxx_rtc_read_alarm(struct device *dev, struct rtc_wkalrm *alarm)
 {
 	struct mc13xxx_rtc *priv = dev_get_drvdata(dev);
-	unsigned seconds, days;
+	unsigned int seconds, days;
 	time64_t s1970;
 	int enabled, pending;
 	int ret;