irqchip/irq-renesas-h8s: Constify irq_domain_ops

struct irq_domain_ops is not modified, so it can be made const.

Cc: Yoshinori Sato <ysato@users.sourceforge.jp>
Cc: uclinux-h8-devel@lists.sourceforge.jp
Signed-off-by: Tobias Klauser <tklauser@distanz.ch>
Signed-off-by: Marc Zyngier <marc.zyngier@arm.com>

drivers/irqchip/irq-renesas-h8s.c

@@ -73,7 +73,7 @@ static __init int irq_map(struct irq_domain *h, unsigned int virq,
        return 0;
 }
 
-static struct irq_domain_ops irq_ops = {
+static const struct irq_domain_ops irq_ops = {
        .map    = irq_map,
        .xlate  = irq_domain_xlate_onecell,
 };