hwmon: (mcp3021) replace S_IRUGO with 0444

Replace S_IRUGO with the better readable 0444.
This fixes a checkpatch warning.
Signed-off-by: NClemens Gruber <clemens.gruber@pqgruber.com>
Signed-off-by: NGuenter Roeck <linux@roeck-us.net>

drivers/hwmon/mcp3021.c

@@ -99,7 +99,7 @@ static ssize_t show_in_input(struct device *dev, struct device_attribute *attr,
 	return sprintf(buf, "%d\n", in_input);
 }
 
-static DEVICE_ATTR(in0_input, S_IRUGO, show_in_input, NULL);
+static DEVICE_ATTR(in0_input, 0444, show_in_input, NULL);
 
 static int mcp3021_probe(struct i2c_client *client,
 				const struct i2c_device_id *id)