hwmon: (lm85) Support different PWM frequency tables

The Analog Devices and SMSC devices supported by the lm85 driver do
not have the same PWM frequency table as the National Semiconductor
devices. Add support for per-device frequency tables.

Signed-off-by: Jean Delvare <khali@linux-fr.org>
Acked-by: Herbert Poetzl <herbert@13thfloor.at>