pinctrl: ralink: Check for null return of devm_kcalloc

Because of the possible failure of the allocation, data->domains might
be NULL pointer and will cause the dereference of the NULL pointer
later.
Therefore, it might be better to check it and directly return -ENOMEM
without releasing data manually if fails, because the comment of the
devm_kmalloc() says "Memory allocated with this function is
automatically freed on driver detach.".

Fixes: a86854d ("treewide: devm_kzalloc() -> devm_kcalloc()")
Reported-by: Hacash Robot <hacashRobot@santino.com>
Signed-off-by: William Dean <williamsukatube@gmail.com>
Link: https://lore.kernel.org/r/20220710154922.2610876-1-williamsukatube@163.com
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>

Author: William Dean

drivers/pinctrl/ralink/pinctrl-ralink.c

@@ -266,6 +266,8 @@ static int ralink_pinctrl_pins(struct ralink_priv *p)
 						p->func[i]->pin_count,
 						sizeof(int),
 						GFP_KERNEL);
+		if (!p->func[i]->pins)
+			return -ENOMEM;
 		for (j = 0; j < p->func[i]->pin_count; j++)
 			p->func[i]->pins[j] = p->func[i]->pin_first + j;