hwmon: remove () used with return

fix checkpatch ERROR:
return is not a function, parentheses are not required

Signed-off-by: Frans Meulenbroeks <fransmeulenbroeks@gmail.com>
Signed-off-by: Guenter Roeck <guenter.roeck@ericsson.com>
diff --git a/drivers/hwmon/pcf8591.c b/drivers/hwmon/pcf8591.c
index 731b09a..2041155 100644
--- a/drivers/hwmon/pcf8591.c
+++ b/drivers/hwmon/pcf8591.c
@@ -269,9 +269,9 @@
 
 	if ((channel == 2 && input_mode == 2) ||
 	    (channel != 3 && (input_mode == 1 || input_mode == 3)))
-		return (10 * REG_TO_SIGNED(value));
+		return 10 * REG_TO_SIGNED(value);
 	else
-		return (10 * value);
+		return 10 * value;
 }
 
 static const struct i2c_device_id pcf8591_id[] = {