invert power sign (openWB#2215)

Author: ndrsnhs

packages/modules/devices/growatt/growatt/bat.py

@@ -26,9 +26,9 @@ def __init__(self,
     def update(self, client: ModbusTcpClient_) -> None:
         if self.version == GrowattVersion.max_series:
             power_in = client.read_input_registers(
-                1011, ModbusDataType.UINT_32, unit=self.__modbus_id) * -0.1
+                1011, ModbusDataType.UINT_32, unit=self.__modbus_id) * 0.1
             power_out = client.read_input_registers(
-                1009, ModbusDataType.UINT_32, unit=self.__modbus_id) * 0.1
+                1009, ModbusDataType.UINT_32, unit=self.__modbus_id) * -0.1
             power = power_in + power_out
 
             soc = client.read_input_registers(1014, ModbusDataType.UINT_16, unit=self.__modbus_id)