iio: adc: Max9611: checking for ERR_PTR instead of NULL in probe

devm_iio_device_alloc() doesn't return ERR_PTRs, it returns NULLs.

Fixes: 69780a3b ("iio: adc: Add Maxim max9611 ADC driver")
Signed-off-by: Dan Carpenter <dan.carpenter@oracle.com>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

drivers/iio/adc/max9611.c

@@ -536,8 +536,8 @@ static int max9611_probe(struct i2c_client *client,
 	int ret;
 
 	indio_dev = devm_iio_device_alloc(&client->dev, sizeof(*max9611));
-	if (IS_ERR(indio_dev))
-		return PTR_ERR(indio_dev);
+	if (!indio_dev)
+		return -ENOMEM;
 
 	i2c_set_clientdata(client, indio_dev);