gpio: arizona: Support Cirrus Logic CS47L24 and WM1831

The CS47L24 and WM1831 codecs only have two GPIO lines, but are
otherwise similar to the WM8280.

Signed-off-by: Richard Fitzgerald <rf@opensource.wolfsonmicro.com>
Acked-by: Linus Walleij <linus.walleij@linaro.org>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

drivers/gpio/gpio-arizona.c

@@ -122,6 +122,10 @@ static int arizona_gpio_probe(struct platform_device *pdev)
 	case WM1814:
 		arizona_gpio->gpio_chip.ngpio = 5;
 		break;
+	case WM1831:
+	case CS47L24:
+		arizona_gpio->gpio_chip.ngpio = 2;
+		break;
 	default:
 		dev_err(&pdev->dev, "Unknown chip variant %d\n",
 			arizona->type);