ACPI: scan: Fix a memory leak in an error handling path

If 'acpi_device_set_name()' fails, we must free
'acpi_device_bus_id->bus_id' or there is a (potential) memory leak.

Fixes: eb50aaf960 ("ACPI: scan: Use unique number for instance_no")
Signed-off-by: Christophe JAILLET <christophe.jaillet@wanadoo.fr>
Reviewed-by: Andy Shevchenko <andriy.shevchenko@linux.intel.com>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>

drivers/acpi/scan.c

@@ -700,6 +700,7 @@ int acpi_device_add(struct acpi_device *device,
 
 		result = acpi_device_set_name(device, acpi_device_bus_id);
 		if (result) {
+			kfree_const(acpi_device_bus_id->bus_id);
 			kfree(acpi_device_bus_id);
 			goto err_unlock;
 		}