PCI: rzg3s-host: Fix device node reference leak in rzg3s_pcie_host_parse_port()

In rzg3s_pcie_host_parse_port(), of_get_next_child() returns a device node
with an incremented reference count that must be released with
of_node_put(). The current code fails to call of_node_put() which causes a
reference leak.

Use the __free(device_node) attribute to ensure automatic cleanup when the
variable goes out of scope.

Fixes: 7ef502f ("PCI: Add Renesas RZ/G3S host controller driver")
Signed-off-by: Felix Gu <ustc.gu@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Tested-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
Reviewed-by: Claudiu Beznea <claudiu.beznea.uj@bp.renesas.com>
Acked-by: Manivannan Sadhasivam <mani@kernel.org>
Link: https://patch.msgid.link/20260204-rzg3s-v1-1-142bc81c3312@gmail.com

Author: outman119

drivers/pci/controller/pcie-rzg3s-host.c

@@ -1142,7 +1142,8 @@ static int rzg3s_pcie_resets_prepare_and_get(struct rzg3s_pcie_host *host)
 
 static int rzg3s_pcie_host_parse_port(struct rzg3s_pcie_host *host)
 {
-	struct device_node *of_port = of_get_next_child(host->dev->of_node, NULL);
+	struct device_node *of_port __free(device_node) =
+		of_get_next_child(host->dev->of_node, NULL);
 	struct rzg3s_pcie_port *port = &host->port;
 	int ret;