pinctrl: core: handle radix_tree_insert() errors in pinctrl_register_one_pin()

pinctrl_register_one_pin() doesn't check the result of radix_tree_insert()
despite they both may return a negative error code.  Linus Walleij said he
has copied the radix tree code from kernel/irq/ where the functions calling
radix_tree_insert() are *void* themselves; I think it makes more sense to
propagate the errors from radix_tree_insert() upstream if we can do that...

Found by Linux Verification Center (linuxtesting.org) with the Svace static
analysis tool.

Signed-off-by: Sergey Shtylyov <s.shtylyov@omp.ru>
Link: https://lore.kernel.org/r/20230719202253.13469-3-s.shtylyov@omp.ru
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

drivers/pinctrl/core.c

@@ -205,6 +205,7 @@ static int pinctrl_register_one_pin(struct pinctrl_dev *pctldev,
 				    const struct pinctrl_pin_desc *pin)
 {
 	struct pin_desc *pindesc;
+	int error;
 
 	pindesc = pin_desc_get(pctldev, pin->number);
 	if (pindesc) {
@@ -226,18 +227,25 @@ static int pinctrl_register_one_pin(struct pinctrl_dev *pctldev,
 	} else {
 		pindesc->name = kasprintf(GFP_KERNEL, "PIN%u", pin->number);
 		if (!pindesc->name) {
-			kfree(pindesc);
-			return -ENOMEM;
+			error = -ENOMEM;
+			goto failed;
 		}
 		pindesc->dynamic_name = true;
 	}
 
 	pindesc->drv_data = pin->drv_data;
 
-	radix_tree_insert(&pctldev->pin_desc_tree, pin->number, pindesc);
+	error = radix_tree_insert(&pctldev->pin_desc_tree, pin->number, pindesc);
+	if (error)
+		goto failed;
+
 	pr_debug("registered pin %d (%s) on %s\n",
 		 pin->number, pindesc->name, pctldev->desc->name);
 	return 0;
+
+failed:
+	kfree(pindesc);
+	return error;
 }
 
 static int pinctrl_register_pins(struct pinctrl_dev *pctldev,