Remove useless mapping in solar inverter SG800

custom_components/tuya_local/devices/solar_inverter_stepuptech.yaml

@@ -96,8 +96,6 @@ secondary_entities:
         unit: "%"
         optional: true
         class: measurement
-        mapping:
-          - scale: 1
   - entity: sensor
     name: PV current
     class: current