hwmon: (sht3x) convert some of sysfs interface to hwmon

update_interval, temperature/humidity max/min and hyst
were moved to new hwmon interface, and only heater and
repeatability were reserved as non-stardard sysfs interface.
Signed-off-by: JuenKit Yip <JuenKit_Yip@hotmail.com>
Link: https://lore.kernel.org/r/DB4PR10MB626157BC697F2CD6100431359229A@DB4PR10MB6261.EURPRD10.PROD.OUTLOOK.COMSigned-off-by: Guenter Roeck <linux@roeck-us.net>