hwmon: (asus-ec-sensors) Add support for fan cpu opt on AMD 600 motherboards

According to the LibreHardwareMonitor project, LibreHardwareMonitorLib/
Hardware/Motherboard/Lpc/EC/EmbeddedController.cs file, fan cpu opt
is supported by the AMD600 EC. Registers are described as follows.

BoardFamily.Amd600, new Dictionary<ECSensor, EmbeddedControllerSource>
{
{ ECSensor.FanCPUOpt,  new EmbeddedControllerSource
("CPU Optional Fan", SensorType.Fan, 0x00b0, 2) },
}

Add FanCPUOpt support for AMD600.

Signed-off-by: Li XingYang <[email protected]>
[groeck: Massaged subject and description]
Signed-off-by: Guenter Roeck <[email protected]>

Author: Li XingYang

drivers/hwmon/asus-ec-sensors.c

@@ -250,6 +250,8 @@ static const struct ec_sensor_info sensors_family_amd_600[] = {
 		EC_SENSOR("Water_In", hwmon_temp, 1, 0x01, 0x00),
 	[ec_sensor_temp_water_out] =
 		EC_SENSOR("Water_Out", hwmon_temp, 1, 0x01, 0x01),
+	[ec_sensor_fan_cpu_opt] =
+		EC_SENSOR("CPU_Opt", hwmon_fan, 2, 0x00, 0xb0),
 };
 
 static const struct ec_sensor_info sensors_family_intel_300[] = {