hwmon: (max6650) Convert to use devm_hwmon_device_register_with_info

Convert driver to use devm_hwmon_device_register_with_info to simplify
the code and to reduce its size.

Cc: Jean-Francois Dagenais <jeff.dagenais@gmail.com>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>