extcon: max77693: Constify struct regmap_config

The regmap_config struct may be const because it is not modified by the
driver and regmap_init() accepts pointer to const.
Signed-off-by: Krzysztof Kozlowski <k.kozlowski@samsung.com>
Signed-off-by: Chanwoo Choi <cw00.choi@samsung.com>

drivers/extcon/extcon-max77693.c

@@ -1033,7 +1033,7 @@ static irqreturn_t max77693_muic_irq_handler(int irq, void *data)
 	return IRQ_HANDLED;
 }
 
-static struct regmap_config max77693_muic_regmap_config = {
+static const struct regmap_config max77693_muic_regmap_config = {
 	.reg_bits = 8,
 	.val_bits = 8,
 };