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/wm8994-irq.c b/drivers/mfd/wm8994-irq.c
index d3a184a..e74dedd 100644
--- a/drivers/mfd/wm8994-irq.c
+++ b/drivers/mfd/wm8994-irq.c
@@ -193,7 +193,7 @@
 {
 	int ret;
 	unsigned long irqflags;
-	struct wm8994_pdata *pdata = wm8994->dev->platform_data;
+	struct wm8994_pdata *pdata = dev_get_platdata(wm8994->dev);
 
 	if (!wm8994->irq) {
 		dev_warn(wm8994->dev,