iio: chemical: bme680: Make error checks consistent

In the majority of the error checks after a regmap_{read,write}()
operation the following coding style is used:

	ret = regmap_{read,write}(data->regmap, ...);
	if (ret < 0) {
		dev_err(dev, ...);
		return ret;
	}

In this particular case it was different so change it for consistency.
Signed-off-by: Vasileios Amoiridis <vassilisamir@gmail.com>
Link: https://patch.msgid.link/20240609233826.330516-11-vassilisamir@gmail.comSigned-off-by: Jonathan Cameron <Jonathan.Cameron@huawei.com>

drivers/iio/chemical/bme680_core.c

@@ -517,10 +517,12 @@ static int bme680_chip_config(struct bme680_data *data)
 	ret = regmap_write_bits(data->regmap, BME680_REG_CTRL_MEAS,
 				BME680_OSRS_TEMP_MASK | BME680_OSRS_PRESS_MASK,
 				osrs);
-	if (ret < 0)
+	if (ret < 0) {
 		dev_err(dev, "failed to write ctrl_meas register\n");
+		return ret;
+	}
 
-	return ret;
+	return 0;
 }
 
 static int bme680_gas_config(struct bme680_data *data)