hwmon: (nct6775) Expand scope of supported chips

NCT6775, NCT6776, and NCT6779 have a number of variants with the same
chip ID but different chip labels. Add text "or compatible" to the
message displayed when the driver is loaded and rephrase the Kconfig
entry to reflect that it also supports compatible chips.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>