hwmon: (w83627ehf) Remove code not needed after nct677* removal

Now the nct677* are gone, we can clean up some flags that are
always the same now and simplify some code.
Signed-off-by: Dr. David Alan Gilbert <linux@treblig.org>
Link: https://lore.kernel.org/r/20191225023225.2785-3-linux@treblig.orgSigned-off-by: Guenter Roeck <linux@roeck-us.net>