Wonderwall Bornholm: invert light control

The display control is more of a "night mode" switch, so on when the light
is off, and off when it is on.

Issue #2400

custom_components/tuya_local/devices/klarstein_wonderwall_bornholm.yaml

@@ -52,6 +52,11 @@ secondary_entities:
       - id: 10
         type: boolean
         name: switch
+        mapping:
+          - dps_val: true
+            value: false
+          - dps_val: false
+            value: true
   - entity: select
     translation_key: timer
     category: config