hwmon: (i5500_temp) Convert to devm_hwmon_device_register_with_groups

Use devm_hwmon_device_register_with_groups() to simplify the code a
bit.

Signed-off-by: Jean Delvare <jdelvare@suse.de>
Cc: Romain Dolbeau <romain@dolbeau.org>
Reviewed-by: Guenter Roeck <linux@roeck-us.net>