leds: flash: mt6360: Fix device_for_each_child_node() refcounting in error paths

The device_for_each_child_node() macro requires explicit calls to
fwnode_handle_put() upon early exits to avoid memory leaks, and in
this case the error paths are handled after jumping to
'out_flash_realease', which misses that required call to
to decrement the refcount of the child node.

A more elegant and robust solution is using the scoped variant of the
loop, which automatically handles such early exits.

Fix the child node refcounting in the error paths by using
device_for_each_child_node_scoped().

Cc: stable@vger.kernel.org
Fixes: 679f865 ("leds: Add mt6360 driver")
Signed-off-by: Javier Carrasco <javier.carrasco.cruz@gmail.com>
Link: https://lore.kernel.org/r/20240927-leds_device_for_each_child_node_scoped-v1-1-95c0614b38c8@gmail.com
Signed-off-by: Lee Jones <lee@kernel.org>

Author: javiercarrascocruz

drivers/leds/flash/leds-mt6360.c

@@ -784,7 +784,6 @@ static void mt6360_v4l2_flash_release(struct mt6360_priv *priv)
 static int mt6360_led_probe(struct platform_device *pdev)
 {
 	struct mt6360_priv *priv;
-	struct fwnode_handle *child;
 	size_t count;
 	int i = 0, ret;
 
@@ -811,7 +810,7 @@ static int mt6360_led_probe(struct platform_device *pdev)
 		return -ENODEV;
 	}
 
-	device_for_each_child_node(&pdev->dev, child) {
+	device_for_each_child_node_scoped(&pdev->dev, child) {
 		struct mt6360_led *led = priv->leds + i;
 		struct led_init_data init_data = { .fwnode = child, };
 		u32 reg, led_color;