Merge branch 'acpi-scan'

* acpi-scan:
ACPI / scan: Fix NULL pointer dereference in acpi_companion_match()

drivers/acpi/scan.c

···
 static struct acpi_device *acpi_companion_match(const struct device *dev)
 {
 	struct acpi_device *adev;
+	struct mutex *physical_node_lock;
 
 	adev = ACPI_COMPANION(dev);
 	if (!adev)
···
 	if (list_empty(&adev->pnp.ids))
 		return NULL;
 
-	mutex_lock(&adev->physical_node_lock);
+	physical_node_lock = &adev->physical_node_lock;
+	mutex_lock(physical_node_lock);
 	if (list_empty(&adev->physical_node_list)) {
 		adev = NULL;
 	} else {
···
 		if (node->dev != dev)
 			adev = NULL;
 	}
-	mutex_unlock(&adev->physical_node_lock);
+	mutex_unlock(physical_node_lock);
 
 	return adev;
 }