pinctrl: cirrus: Fix fwnode leak in cs42l43_pin_probe()

The driver calls fwnode_get_named_child_node() which takes a reference
on the child node, but never releases it, which causes a reference leak.

Fix by using devm_add_action_or_reset() to automatically release the
reference when the device is removed.

Fixes: d5282a539297 ("pinctrl: cs42l43: Add support for the cs42l43")
Suggested-by: Charles Keepax <[e-mail]>
Signed-off-by: Haotian Zhang <[e-mail]>
Signed-off-by: Linus Walleij <[e-mail]>

drivers/pinctrl/cirrus/pinctrl-cs42l43.c

···
 	return ret;
 }
 
+static void cs42l43_fwnode_put(void *data)
+{
+	fwnode_handle_put(data);
+}
+
 static int cs42l43_pin_probe(struct platform_device *pdev)
 {
 	struct cs42l43 *cs42l43 = dev_get_drvdata(pdev->dev.parent);
···
 	priv->gpio_chip.ngpio = CS42L43_NUM_GPIOS;
 
 	if (is_of_node(fwnode)) {
-		fwnode = fwnode_get_named_child_node(fwnode, "pinctrl");
+		struct fwnode_handle *child;
 
-		if (fwnode && !fwnode->dev)
-			fwnode->dev = priv->dev;
+		child = fwnode_get_named_child_node(fwnode, "pinctrl");
+		if (child) {
+			ret = devm_add_action_or_reset(&pdev->dev,
+				cs42l43_fwnode_put, child);
+			if (ret) {
+				fwnode_handle_put(child);
+				return ret;
+			}
+			if (!child->dev)
+				child->dev = priv->dev;
+			fwnode = child;
+		}
 	}
 
 	priv->gpio_chip.fwnode = fwnode;