gpio: use dev_get_platdata()

Use the wrapper function for retrieving the platform data instead of
accessing dev->platform_data directly.

Signed-off-by: Jingoo Han <jg1.han@samsung.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>
diff --git a/drivers/gpio/gpio-sx150x.c b/drivers/gpio/gpio-sx150x.c
index f371732..d2983e9 100644
--- a/drivers/gpio/gpio-sx150x.c
+++ b/drivers/gpio/gpio-sx150x.c
@@ -583,7 +583,7 @@
 	struct sx150x_chip *chip;
 	int rc;
 
-	pdata = client->dev.platform_data;
+	pdata = dev_get_platdata(&client->dev);
 	if (!pdata)
 		return -EINVAL;