hwmon: (pmbus/ltc2978) add support for more parts.

LTC2972, LTC2979, LTC3884, LTC3889, LTC7880, LTM4664, LTM4677,
LTM4678, LTM4680, LTM4700.

Signed-off-by: Mike Jones <michael-a1.jones@analog.com>
Link: https://lore.kernel.org/r/1581032654-4330-1-git-send-email-michael-a1.jones@analog.com


[groeck: Fixed checkpatch issues (long lines, whitespace)]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>