The previous version of the OF code was returning -ENODEV if no
thermal zones description was found or if the lookup of the sensor in
the thermal zones was not found.
The backend drivers are expecting this return value as an information
about skipping the sensor initialization and considered as normal.
Fix the return value by replacing -EINVAL by -ENODEV
Signed-off-by: Daniel Lezcano <daniel.lezcano@xxxxxxxxxx>