pinctrl: core: Make dt_free_map optional

If the pin controller driver is using devm_kzalloc, there may not be
anything to do for dt_free_map. Let's make it optional to avoid
unncessary boilerplate code.
Signed-off-by: Tony Lindgren <tony@atomide.com>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/core.c

@@ -1913,9 +1913,6 @@ static int pinctrl_check_ops(struct pinctrl_dev *pctldev)
 	    !ops->get_group_name)
 		return -EINVAL;
 
-	if (ops->dt_node_to_map && !ops->dt_free_map)
-		return -EINVAL;
-
 	return 0;
 }
 

drivers/pinctrl/devicetree.c

@@ -42,6 +42,7 @@ static void dt_free_map(struct pinctrl_dev *pctldev,
 {
 	if (pctldev) {
 		const struct pinctrl_ops *ops = pctldev->desc->pctlops;
+		if (ops->dt_free_map)
 			ops->dt_free_map(pctldev, map, num_maps);
 	} else {
 		/* There is no pctldev for PIN_MAP_TYPE_DUMMY_STATE */