rtc: rtc-puv3: remove unnecessary platform_set_drvdata()

The driver core clears the driver data to NULL after device_release or
on probe failure, since commit 0998d063100 ("device-core: Ensure drvdata
= NULL when no driver is bound").  Thus, it is not needed to manually
clear the device driver data to NULL.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Acked-by: Guan Xuetao <gxt@mprc.pku.edu.cn>
Signed-off-by: Andrew Morton <akpm@linux-foundation.org>
Signed-off-by: Linus Torvalds <torvalds@linux-foundation.org>
diff --git a/drivers/rtc/rtc-puv3.c b/drivers/rtc/rtc-puv3.c
index 72f4371..402732c 100644
--- a/drivers/rtc/rtc-puv3.c
+++ b/drivers/rtc/rtc-puv3.c
@@ -224,7 +224,6 @@
 {
 	struct rtc_device *rtc = platform_get_drvdata(dev);
 
-	platform_set_drvdata(dev, NULL);
 	rtc_device_unregister(rtc);
 
 	puv3_rtc_setpie(&dev->dev, 0);