rtc: rtc-wm831x: use devm_request_threaded_irq()

Use devm_request_threaded_irq() to make cleanup paths more simple.
Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>

drivers/rtc/rtc-wm831x.c

@@ -443,7 +443,8 @@ static int wm831x_rtc_probe(struct platform_device *pdev)
 		goto err;
 	}
 
-	ret = request_threaded_irq(alm_irq, NULL, wm831x_alm_irq,
+	ret = devm_request_threaded_irq(&pdev->dev, alm_irq, NULL,
+				wm831x_alm_irq,
 				IRQF_TRIGGER_RISING, "RTC alarm",
 				wm831x_rtc);
 	if (ret != 0) {
@@ -462,9 +463,7 @@ static int wm831x_rtc_probe(struct platform_device *pdev)
 static int wm831x_rtc_remove(struct platform_device *pdev)
 {
 	struct wm831x_rtc *wm831x_rtc = platform_get_drvdata(pdev);
-	int alm_irq = platform_get_irq_byname(pdev, "ALM");
 
-	free_irq(alm_irq, wm831x_rtc);
 	rtc_device_unregister(wm831x_rtc->rtc);
 
 	return 0;