dt-bindings: Add LM96000 as a trivial device

The LM96000 is a temperature sensor and fan controller based
on the LM85.

Signed-off-by: Jeremy Gebben <jgebben@sweptlaser.com>
Reviewed-by: Rob Herring <robh@kernel.org>
Signed-off-by: Guenter Roeck <linux@roeck-us.net>