i2c: 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: Wolfram Sang <wsa@the-dreams.de>
diff --git a/drivers/i2c/muxes/i2c-mux-gpio.c b/drivers/i2c/muxes/i2c-mux-gpio.c
index 5a0ce00..6a206e8 100644
--- a/drivers/i2c/muxes/i2c-mux-gpio.c
+++ b/drivers/i2c/muxes/i2c-mux-gpio.c
@@ -148,12 +148,14 @@
 
 	platform_set_drvdata(pdev, mux);
 
-	if (!pdev->dev.platform_data) {
+	if (!dev_get_platdata(&pdev->dev)) {
 		ret = i2c_mux_gpio_probe_dt(mux, pdev);
 		if (ret < 0)
 			return ret;
-	} else
-		memcpy(&mux->data, pdev->dev.platform_data, sizeof(mux->data));
+	} else {
+		memcpy(&mux->data, dev_get_platdata(&pdev->dev),
+			sizeof(mux->data));
+	}
 
 	/*
 	 * If a GPIO chip name is provided, the GPIO pin numbers provided are