leds: 88pm860x: Use of_get_child_by_name

Use of_get_child_by_name to obtain reference to charger node instead of
of_find_node_by_name which can walk outside of the parent node.

Signed-off-by: Krzysztof Kozlowski <[e-mail]>
Signed-off-by: Bryan Wu <[e-mail]>

drivers/leds/leds-88pm860x.c

···
 	nproot = of_node_get(pdev->dev.parent->of_node);
 	if (!nproot)
 		return -ENODEV;
-	nproot = of_find_node_by_name(nproot, "leds");
+	nproot = of_get_child_by_name(nproot, "leds");
 	if (!nproot) {
 		dev_err(&pdev->dev, "failed to find leds node\n");
 		return -ENODEV;