hwmon: (smsc47m1) restore missing name attribute

The smsc47m1 driver no longer creates the name attribute used by
libsensors to identify chip types. It was lost during the conversion
to a platform driver. I was fooled by the fact that we do have a
group with all attributes, but only to delete them all at once. The
group is not used to create the attributes, so we have to explicitly
create the name attribute.

This fixes lm-sensors ticket #2236:
http://lm-sensors.org/ticket/2236



Signed-off-by: Jean Delvare <khali@linux-fr.org>
Signed-off-by: Mark M. Hoffman <mhoffman@lightlink.com>