thermal/drivers/hwmon: Cleanup coding style a bit

Function thermal_add_hwmon_sysfs, hwmon will be NULL when
new_hwmon_device = 0, so there is no need to check, kfree will
handle NULL point.

Signed-off-by: Bernard Zhao <[e-mail]>
Signed-off-by: Daniel Lezcano <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]

drivers/thermal/thermal_hwmon.c

···
 	if (new_hwmon_device)
 		hwmon_device_unregister(hwmon->device);
  free_mem:
-	if (new_hwmon_device)
-		kfree(hwmon);
+	kfree(hwmon);
 
 	return result;
 }