pinctrl: samsung: Constify samsung_pin_bank_type struct

This structure is not intended to be modified at runtime and functions
as constant data shared between multiple pin banks. This patch makes all
instances of it constant across the driver.

Signed-off-by: Tomasz Figa <tomasz.figa@gmail.com>
diff --git a/drivers/pinctrl/samsung/pinctrl-s3c24xx.c b/drivers/pinctrl/samsung/pinctrl-s3c24xx.c
index e389259..9db6cf5 100644
--- a/drivers/pinctrl/samsung/pinctrl-s3c24xx.c
+++ b/drivers/pinctrl/samsung/pinctrl-s3c24xx.c
@@ -44,12 +44,12 @@
 #define EINT_EDGE_BOTH		6
 #define EINT_MASK		0xf
 
-static struct samsung_pin_bank_type bank_type_1bit = {
+static const struct samsung_pin_bank_type bank_type_1bit = {
 	.fld_width = { 1, 1, },
 	.reg_offset = { 0x00, 0x04, },
 };
 
-static struct samsung_pin_bank_type bank_type_2bit = {
+static const struct samsung_pin_bank_type bank_type_2bit = {
 	.fld_width = { 2, 1, 2, },
 	.reg_offset = { 0x00, 0x04, 0x08, },
 };
@@ -143,7 +143,7 @@
 static void s3c24xx_eint_set_function(struct samsung_pinctrl_drv_data *d,
 					struct samsung_pin_bank *bank, int pin)
 {
-	struct samsung_pin_bank_type *bank_type = bank->type;
+	const struct samsung_pin_bank_type *bank_type = bank->type;
 	unsigned long flags;
 	void __iomem *reg;
 	u8 shift;