rtc: Use dev_get_drvdata()

Using dev_get_drvdata directly.

Cc: Alessandro Zummo <a.zummo@towertech.it>
Cc: Alexandre Belloni <alexandre.belloni@bootlin.com>
Cc: linux-rtc@vger.kernel.org
Signed-off-by: Kefeng Wang <wangkefeng.wang@huawei.com>
Signed-off-by: Alexandre Belloni <alexandre.belloni@bootlin.com>
diff --git a/drivers/rtc/rtc-pxa.c b/drivers/rtc/rtc-pxa.c
index e1887b8..d476673 100644
--- a/drivers/rtc/rtc-pxa.c
+++ b/drivers/rtc/rtc-pxa.c
@@ -145,8 +145,7 @@ static void rtsr_set_bits(struct pxa_rtc *pxa_rtc, u32 mask)
 
 static irqreturn_t pxa_rtc_irq(int irq, void *dev_id)
 {
-	struct platform_device *pdev = to_platform_device(dev_id);
-	struct pxa_rtc *pxa_rtc = platform_get_drvdata(pdev);
+	struct pxa_rtc *pxa_rtc = dev_get_drvdata(dev_id);
 	u32 rtsr;
 	unsigned long events = 0;