pinctrl: meson: meson: Add of_node_put() before return

Each iteration of for_each_child_of_node puts the previous node, but in
the case of a return from the middle of the loop, there is no put, thus
causing a memory leak. Hence add an of_node_put before the return.
Issue found with Coccinelle.

Signed-off-by: Nishka Dasgupta <nishkadg.linux@gmail.com>
Link: https://lore.kernel.org/r/20190815060718.3286-1-nishkadg.linux@gmail.com
Reviewed-by: Neil Armstrong <narmstrong@baylibre.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/meson/pinctrl-meson.c

@@ -651,6 +651,7 @@ static int meson_pinctrl_parse_dt(struct meson_pinctrl *pc,
 			continue;
 		if (gpio_np) {
 			dev_err(pc->dev, "multiple gpio nodes\n");
+			of_node_put(np);
 			return -EINVAL;
 		}
 		gpio_np = np;