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>
diff --git a/drivers/mfd/da9055-core.c b/drivers/mfd/da9055-core.c
index b4d920c..177e65a 100644
--- a/drivers/mfd/da9055-core.c
+++ b/drivers/mfd/da9055-core.c
@@ -222,7 +222,7 @@
 	}
 }
 
-static struct regmap_irq da9055_irqs[] = {
+static const struct regmap_irq da9055_irqs[] = {
 	[DA9055_IRQ_NONKEY] = {
 		.reg_offset = 0,
 		.mask = DA9055_IRQ_NONKEY_MASK,
@@ -245,7 +245,7 @@
 	},
 };
 
-struct regmap_config da9055_regmap_config = {
+const struct regmap_config da9055_regmap_config = {
 	.reg_bits = 8,
 	.val_bits = 8,
 
@@ -367,7 +367,7 @@
 	},
 };
 
-static struct regmap_irq_chip da9055_regmap_irq_chip = {
+static const struct regmap_irq_chip da9055_regmap_irq_chip = {
 	.name = "da9055_irq",
 	.status_base = DA9055_REG_EVENT_A,
 	.mask_base = DA9055_REG_IRQ_MASK_A,