i8k: Drop all labels

Labels are known to be wrong for several Dell laptops.
For example, a single fan may be shown as right fan when in reality
it sits on the left side of the chassis. Drop all labels to avoid
such inaccuracies. Users can select labels in the sensors configuration
file instead if desired.

Signed-off-by: Guenter Roeck <linux@roeck-us.net>
Cc: Andreas Mohr <andi@lisas.de>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>