Input: gpio_keys - fix leaking DT node references

for_each_available_child_of_node(node, pp) takes reference to 'pp' and
drops it when attempting next iteration. However if we exit the loop early
we need to drop the reference ourselves.

Tested-by: Mika Westerberg <[e-mail]>
Signed-off-by: Dmitry Torokhov <[e-mail]>

drivers/input/keyboard/gpio_keys.c

···
 					dev_err(dev,
 						"Failed to get gpio flags, error: %d\n",
 						error);
+				of_node_put(pp);
 				return ERR_PTR(error);
 			}
 		} else {
···
 
 		if (!gpio_is_valid(button->gpio) && !button->irq) {
 			dev_err(dev, "Found button without gpios or irqs\n");
+			of_node_put(pp);
 			return ERR_PTR(-EINVAL);
 		}
 
 		if (of_property_read_u32(pp, "linux,code", &button->code)) {
 			dev_err(dev, "Button without keycode: 0x%x\n",
 				button->gpio);
+			of_node_put(pp);
 			return ERR_PTR(-EINVAL);
 		}