pinctrl: cirrus: Fix fwnode leak in cs42l43_pin_probe()

pinctrl: cirrus: Fix fwnode leak in cs42l43_pin_probe()

The driver calls fwnode_get_named_child_node() which takes a reference
on the child node, but never releases it, which causes a reference leak.

Fix by using devm_add_action_or_reset() to automatically release the
reference when the device is removed.

Fixes: d5282a539297 ("pinctrl: cs42l43: Add support for the cs42l43")
Suggested-by: Charles Keepax <ckeepax@opensource.cirrus.com>
Signed-off-by: Haotian Zhang <vulab@iscas.ac.cn>
Signed-off-by: Linus Walleij <linus.walleij@linaro.org>