leds: various: fix OF node leaks

Fix OF node leaks by calling of_node_put in
for_each_available_child_of_node when the cycle breaks or returns.

Signed-off-by: Marek Behún <marek.behun@nic.cz>
Cc: Nikita Travkin <nikitos.tr@gmail.com>
Cc: Milo Kim <milo.kim@ti.com>
Cc: Dan Murphy <dmurphy@ti.com>
Signed-off-by: Pavel Machek <pavel@ucw.cz>
Not-for-stable: untested, theoretical, insignificant leaks