dt-bindings: thermal: Drop 'trips' node as required

It is possible to have thermal zones which don't have any trip points.
These zones in effect simply represent a temperature sensor without any
action associated with it. While the schema has always required a
'trips' node, users have existed for a long time without it. Update the
schema to match reality.

Signed-off-by: Rob Herring (Arm) <[email protected]>
Reviewed-by: Krzysztof Kozlowski <[email protected]>
Link: https://lore.kernel.org/r/[email protected]
Signed-off-by: Daniel Lezcano <[email protected]>

Author: robherring

Documentation/devicetree/bindings/thermal/thermal-zones.yaml

@@ -232,7 +232,6 @@ patternProperties:
 
     required:
       - thermal-sensors
-      - trips
 
     additionalProperties: false