gpio: rmobile: Add RCar Gen2 compatible string

Add DT compatible string for RCar Gen2.
Signed-off-by: NMarek Vasut <marek.vasut+renesas@gmail.com>
Cc: Nobuhiro Iwamatsu <iwamatsu@nigauri.org>

drivers/gpio/gpio-rcar.c

@@ -176,6 +176,7 @@ static const struct udevice_id rcar_gpio_ids[] = {
 	{ .compatible = "renesas,gpio-r8a7796" },
 	{ .compatible = "renesas,gpio-r8a77970" },
 	{ .compatible = "renesas,gpio-r8a77995" },
+	{ .compatible = "renesas,rcar-gen2-gpio" },
 	{ .compatible = "renesas,rcar-gen3-gpio" },
 	{ /* sentinel */ }
 };