mfd: max14577: Make of_device_id array const

Array of struct of_device_id should be const as expected by both
of_match_table field and of_match_device() call.

Signed-off-by: Krzysztof Kozlowski <[e-mail]>
Signed-off-by: Lee Jones <[e-mail]>

drivers/mfd/max14577.c

···
 	},
 };
 
-static struct of_device_id max14577_dt_match[] = {
+static const struct of_device_id max14577_dt_match[] = {
 	{
 		.compatible = "maxim,max14577",
 		.data = (void *)MAXIM_DEVICE_TYPE_MAX14577,