pinctrl: bcm2835: Accept fewer than expected IRQs

The downstream .dts files only request two GPIO IRQs. Truncate the
array of parent IRQs when irq_of_parse_and_map returns 0.

Signed-off-by: Phil Elwell <[e-mail]>
Signed-off-by: Ivan T. Ivanov <[e-mail]>
Reviewed-by: Florian Fainelli <[e-mail]>
Link: https://lore.kernel.org/r/[e-mail]
Signed-off-by: Linus Walleij <[e-mail]>

drivers/pinctrl/bcm/pinctrl-bcm2835.c

···
 		char *name;
 
 		girq->parents[i] = irq_of_parse_and_map(np, i);
-		if (!is_7211)
+		if (!is_7211) {
+			if (!girq->parents[i]) {
+				girq->num_parents = i;
+				break;
+			}
 			continue;
-
+		}
 		/* Skip over the all banks interrupts */
 		pc->wake_irq[i] = irq_of_parse_and_map(np, i +
 						       BCM2835_NUM_IRQS + 1);