watchdog: twl4030: Remove redundant platform_set_drvdata()

Commit 0998d06310 (device-core: Ensure drvdata = NULL when no
driver is bound) removes the need to set driver data field to
NULL.

Signed-off-by: Sachin Kamat <[e-mail]>
Cc: Timo Kokkonen <[e-mail]>
Signed-off-by: Wim Van Sebroeck <[e-mail]>

drivers/watchdog/twl4030_wdt.c

···
 	twl4030_wdt_stop(wdt);
 
 	ret = watchdog_register_device(wdt);
-	if (ret) {
-		platform_set_drvdata(pdev, NULL);
+	if (ret)
 		return ret;
-	}
 
 	return 0;
 }
···
 	struct watchdog_device *wdt = platform_get_drvdata(pdev);
 
 	watchdog_unregister_device(wdt);
-	platform_set_drvdata(pdev, NULL);
 
 	return 0;
 }