iio:magnetometer:bmc150_magn: output intended variable

According to the debug/error string, the content of chip_id is supposed to
be output, rather than the return value of the previous operation.

Fixes: c91746a2 ("iio: magn: Add support for BMC150 magnetometer")
Signed-off-by: Hartmut Knaack <knaack.h@gmx.de>
Signed-off-by: Jonathan Cameron <jic23@kernel.org>

drivers/iio/magnetometer/bmc150_magn.c

@@ -706,11 +706,11 @@ static int bmc150_magn_init(struct bmc150_magn_data *data)
 		goto err_poweroff;
 	}
 	if (chip_id != BMC150_MAGN_CHIP_ID_VAL) {
-		dev_err(&data->client->dev, "Invalid chip id 0x%x\n", ret);
+		dev_err(&data->client->dev, "Invalid chip id 0x%x\n", chip_id);
 		ret = -ENODEV;
 		goto err_poweroff;
 	}
-	dev_dbg(&data->client->dev, "Chip id %x\n", ret);
+	dev_dbg(&data->client->dev, "Chip id %x\n", chip_id);
 
 	preset = bmc150_magn_presets_table[BMC150_MAGN_DEFAULT_PRESET];
 	ret = bmc150_magn_set_odr(data, preset.odr);