MIPS: OCTEON: Constify static irq_domain_ops

The only usage of these structs is to pass their address to either
irq_domain_add_tree() or irq_domain_create_linear(), both which takes
pointers to const struct irq_domain_ops. Make them const to allow the
compiler to put them in read-only memory.
Signed-off-by: Rikard Falkeborn <rikard.falkeborn@gmail.com>
Signed-off-by: Thomas Bogendoerfer <tsbogend@alpha.franken.de>

arch/mips/cavium-octeon/octeon-irq.c

@@ -1274,13 +1274,13 @@ static int octeon_irq_gpio_map(struct irq_domain *d,
 	return r;
 }
 
-static struct irq_domain_ops octeon_irq_domain_ciu_ops = {
+static const struct irq_domain_ops octeon_irq_domain_ciu_ops = {
 	.map = octeon_irq_ciu_map,
 	.unmap = octeon_irq_free_cd,
 	.xlate = octeon_irq_ciu_xlat,
 };
 
-static struct irq_domain_ops octeon_irq_domain_gpio_ops = {
+static const struct irq_domain_ops octeon_irq_domain_gpio_ops = {
 	.map = octeon_irq_gpio_map,
 	.unmap = octeon_irq_free_cd,
 	.xlate = octeon_irq_gpio_xlat,
@@ -1974,7 +1974,7 @@ static int octeon_irq_ciu2_map(struct irq_domain *d,
 	return 0;
 }
 
-static struct irq_domain_ops octeon_irq_domain_ciu2_ops = {
+static const struct irq_domain_ops octeon_irq_domain_ciu2_ops = {
 	.map = octeon_irq_ciu2_map,
 	.unmap = octeon_irq_free_cd,
 	.xlate = octeon_irq_ciu2_xlat,
@@ -2226,7 +2226,7 @@ static int octeon_irq_cib_map(struct irq_domain *d,
 	return 0;
 }
 
-static struct irq_domain_ops octeon_irq_domain_cib_ops = {
+static const struct irq_domain_ops octeon_irq_domain_cib_ops = {
 	.map = octeon_irq_cib_map,
 	.unmap = octeon_irq_free_cd,
 	.xlate = octeon_irq_cib_xlat,
@@ -2578,7 +2578,7 @@ static int octeon_irq_ciu3_map(struct irq_domain *d,
 	return octeon_irq_ciu3_mapx(d, virq, hw, &octeon_irq_chip_ciu3);
 }
 
-static struct irq_domain_ops octeon_dflt_domain_ciu3_ops = {
+static const struct irq_domain_ops octeon_dflt_domain_ciu3_ops = {
 	.map = octeon_irq_ciu3_map,
 	.unmap = octeon_irq_free_cd,
 	.xlate = octeon_irq_ciu3_xlat,