hwmon: add SCH5317 to smsc47b397 driver

This patch adds the SMSC SCH5317 chip (device ID 0x85) as a supported
device to the smsc47b397 driver.

Signed-off-by: Juerg Haefliger <juergh at gmail.com>
Signed-off-by: Mark M. Hoffman <mhoffman@lightlink.com>