pinctrl: fix a memleak when freeing maps

We forgot to free the node itself when free:ing a map.
Reported-by: xulinuxkernel <xulinuxkernel@gmail.com>
Reviewed-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/core.c

@@ -1193,6 +1193,7 @@ void pinctrl_unregister_map(struct pinctrl_map const *map)
 	list_for_each_entry(maps_node, &pinctrl_maps, node) {
 		if (maps_node->maps == map) {
 			list_del(&maps_node->node);
+			kfree(maps_node);
 			mutex_unlock(&pinctrl_maps_mutex);
 			return;
 		}