gpio: mvebu: Do not hard code error code

Return the appropriate error code instead of hardcoding it.

Signed-off-by: Sachin Kamat <[e-mail]>
Signed-off-by: Linus Walleij <[e-mail]>

drivers/gpio/gpio-mvebu.c

···
 	mvchip->irqbase = irq_alloc_descs(-1, 0, ngpios, -1);
 	if (mvchip->irqbase < 0) {
 		dev_err(&pdev->dev, "no irqs\n");
-		return -ENOMEM;
+		return mvchip->irqbase;
 	}
 
 	gc = irq_alloc_generic_chip("mvebu_gpio_irq", 2, mvchip->irqbase,