hwmon: (gpd-fan) Fix error handling in gpd_fan_probe()

devm_request_region() returns a NULL pointer on error, not an ERR_PTR().
Handle it accordingly.

Also fix error return from the call to devm_hwmon_device_register_with_info().

Fixes: 0ab88e2 ("hwmon: add GPD devices sensor driver")
Signed-off-by: Harshit Mogalapalli <harshit.m.mogalapalli@oracle.com>
Reviewed-by: Cryolitia PukNgae <cryolitia@uniontech.com>
Link: https://lore.kernel.org/r/20251010204447.94343-1-harshit.m.mogalapalli@oracle.com
[groeck: Updated subject to improve readability]
Signed-off-by: Guenter Roeck <linux@roeck-us.net>

Author: harshimogalapalli

drivers/hwmon/gpd-fan.c

@@ -621,8 +621,8 @@ static int gpd_fan_probe(struct platform_device *pdev)
 
 	region = devm_request_region(dev, res->start,
 				     resource_size(res), DRIVER_NAME);
-	if (IS_ERR(region))
-		return dev_err_probe(dev, PTR_ERR(region),
+	if (!region)
+		return dev_err_probe(dev, -EBUSY,
 				     "Failed to request region\n");
 
 	hwdev = devm_hwmon_device_register_with_info(dev,
@@ -631,7 +631,7 @@ static int gpd_fan_probe(struct platform_device *pdev)
 						     &gpd_fan_chip_info,
 						     NULL);
 	if (IS_ERR(hwdev))
-		return dev_err_probe(dev, PTR_ERR(region),
+		return dev_err_probe(dev, PTR_ERR(hwdev),
 				     "Failed to register hwmon device\n");
 
 	return 0;