mfd: Constify regmap and irq configuration data

Constify in various drivers configuration data which is not modified:
 - regmap_irq_chip,
 - individual regmap_irq's in array,
 - regmap_config,
 - irq_domain_ops,

Signed-off-by: Krzysztof Kozlowski <k.kozlowski.k@gmail.com>
Signed-off-by: Lee Jones <lee.jones@linaro.org>

drivers/mfd/tc3589x.c

@@ -233,7 +233,7 @@ static void tc3589x_irq_unmap(struct irq_domain *d, unsigned int virq)
 	irq_set_chip_data(virq, NULL);
 }
 
-static struct irq_domain_ops tc3589x_irq_ops = {
+static const struct irq_domain_ops tc3589x_irq_ops = {
 	.map    = tc3589x_irq_map,
 	.unmap  = tc3589x_irq_unmap,
 	.xlate  = irq_domain_xlate_onecell,