irqchip/imx-irqsteer: Constify irq_chip struct

The imx_irqsteer_irq_chip struct is constant data.
Signed-off-by: Lucas Stach <l.stach@pengutronix.de>
Signed-off-by: Marc Zyngier <maz@kernel.org>
Link: https://lore.kernel.org/r/20220406163701.1277930-1-l.stach@pengutronix.de

drivers/irqchip/irq-imx-irqsteer.c

@@ -70,7 +70,7 @@ static void imx_irqsteer_irq_mask(struct irq_data *d)
 	raw_spin_unlock_irqrestore(&data->lock, flags);
 }
 
-static struct irq_chip imx_irqsteer_irq_chip = {
+static const struct irq_chip imx_irqsteer_irq_chip = {
 	.name		= "irqsteer",
 	.irq_mask	= imx_irqsteer_irq_mask,
 	.irq_unmask	= imx_irqsteer_irq_unmask,