mfd: 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: Lee Jones <lee.jones@linaro.org>
diff --git a/drivers/mfd/wm831x-irq.c b/drivers/mfd/wm831x-irq.c
index 804e56e..64e512e 100644
--- a/drivers/mfd/wm831x-irq.c
+++ b/drivers/mfd/wm831x-irq.c
@@ -571,7 +571,7 @@
 
 int wm831x_irq_init(struct wm831x *wm831x, int irq)
 {
-	struct wm831x_pdata *pdata = wm831x->dev->platform_data;
+	struct wm831x_pdata *pdata = dev_get_platdata(wm831x->dev);
 	struct irq_domain *domain;
 	int i, ret, irq_base;