i2c: core: Do not dereference fwnode in struct device

In order to make the underneath API easier to change in the future,
prevent users from dereferencing fwnode from struct device.
Instead, use the specific device_set_node() API for that.

Tested-by: Tomi Valkeinen <[e-mail]>
Reviewed-by: Sakari Ailus <[e-mail]>
Acked-by: Sakari Ailus <[e-mail]>
Signed-off-by: Andy Shevchenko <[e-mail]>
Signed-off-by: Wolfram Sang <[e-mail]>

drivers/i2c/i2c-core-base.c

···
 struct i2c_client *
 i2c_new_client_device(struct i2c_adapter *adap, struct i2c_board_info const *info)
 {
+	struct fwnode_handle *fwnode;
 	struct i2c_client *client;
 	bool need_put = false;
 	int status;
···
 	client->dev.parent = &client->adapter->dev;
 	client->dev.bus = &i2c_bus_type;
 	client->dev.type = &i2c_client_type;
-	client->dev.of_node = of_node_get(info->of_node);
-	client->dev.fwnode = info->fwnode;
 
 	device_enable_async_suspend(&client->dev);
+
+	fwnode = info->fwnode ?: of_fwnode_handle(info->of_node);
+	device_set_node(&client->dev, fwnode_handle_get(fwnode));
 
 	if (info->swnode) {
 		status = device_add_software_node(&client->dev, info->swnode);
···
 			dev_err(&adap->dev,
 				"Failed to add software node to client %s: %d\n",
 				client->name, status);
-			goto out_err_put_of_node;
+			goto out_err_put_fwnode;
 		}
 	}
 
···
 out_remove_swnode:
 	device_remove_software_node(&client->dev);
 	need_put = true;
-out_err_put_of_node:
-	of_node_put(info->of_node);
+out_err_put_fwnode:
+	fwnode_handle_put(fwnode);
 out_err:
 	dev_err(&adap->dev,
 		"Failed to register i2c client %s at 0x%02x (%d)\n",
···
 		return;
 
 	fwnode = dev_fwnode(&client->dev);
-	if (is_of_node(fwnode)) {
+	if (is_of_node(fwnode))
 		of_node_clear_flag(to_of_node(fwnode), OF_POPULATED);
-		of_node_put(client->dev.of_node);
-	} else if (is_acpi_device_node(fwnode)) {
+	else if (is_acpi_device_node(fwnode))
 		acpi_device_clear_enumerated(to_acpi_device_node(fwnode));
-	}
+	fwnode_handle_put(fwnode);
 
 	device_remove_software_node(&client->dev);
 	device_unregister(&client->dev);

drivers/i2c/i2c-core-of.c

···
 	}
 
 	info->addr = addr;
-	info->of_node = node;
 	info->fwnode = of_fwnode_handle(node);
 
 	if (of_property_read_bool(node, "host-notify"))