media: i2c: imx290: simplify getting state container

The pointer to 'struct v4l2_subdev' is stored in drvdata via
v4l2_i2c_subdev_init() so there is no point of a dance like:

    struct i2c_client *client = to_i2c_client(struct device *dev)
    struct v4l2_subdev *sd = i2c_get_clientdata(client);

This allows to remove local variable 'client' and few pointer
dereferences.  White at it, use 'dev' directly instead of 'imx290->dev'.
Signed-off-by: Krzysztof Kozlowski <krzk@kernel.org>
Signed-off-by: Sakari Ailus <sakari.ailus@linux.intel.com>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>

drivers/media/i2c/imx290.c

@@ -842,20 +842,19 @@ static int imx290_set_data_lanes(struct imx290 *imx290)
 
 static int imx290_power_on(struct device *dev)
 {
-	struct i2c_client *client = to_i2c_client(dev);
-	struct v4l2_subdev *sd = i2c_get_clientdata(client);
+	struct v4l2_subdev *sd = dev_get_drvdata(dev);
 	struct imx290 *imx290 = to_imx290(sd);
 	int ret;
 
 	ret = clk_prepare_enable(imx290->xclk);
 	if (ret) {
-		dev_err(imx290->dev, "Failed to enable clock\n");
+		dev_err(dev, "Failed to enable clock\n");
 		return ret;
 	}
 
 	ret = regulator_bulk_enable(IMX290_NUM_SUPPLIES, imx290->supplies);
 	if (ret) {
-		dev_err(imx290->dev, "Failed to enable regulators\n");
+		dev_err(dev, "Failed to enable regulators\n");
 		clk_disable_unprepare(imx290->xclk);
 		return ret;
 	}
@@ -872,8 +871,7 @@ static int imx290_power_on(struct device *dev)
 
 static int imx290_power_off(struct device *dev)
 {
-	struct i2c_client *client = to_i2c_client(dev);
-	struct v4l2_subdev *sd = i2c_get_clientdata(client);
+	struct v4l2_subdev *sd = dev_get_drvdata(dev);
 	struct imx290 *imx290 = to_imx290(sd);
 
 	clk_disable_unprepare(imx290->xclk);