gpio-charger: Remove unnecessary platform_set_drvdata()

The driver core clears the driver data to NULL after device_release or on
probe failure, since commit 0998d063
(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>
Signed-off-by: Anton Vorontsov <anton@enomsg.org>

drivers/power/gpio-charger.c

@@ -155,8 +155,6 @@ static int gpio_charger_remove(struct platform_device *pdev)
 
 	gpio_free(gpio_charger->pdata->gpio);
 
-	platform_set_drvdata(pdev, NULL);
-
 	return 0;
 }