[PATCH net 2/2] net: macb: put the "mdio" child node reference on success

macb_mii_init() holds the reference returned by of_get_child_by_name()
for macb_mdiobus_register() and drops it only on the error paths, so
every successful probe leaks a node reference. On a CM5, overlay
removal after four bind cycles reports

  OF: ERROR: memory leak, expected refcount 1 instead of 5

Drop the reference after registration, where __mdiobus_register() has
already taken its own for the lifetime of the bus.

Fixes: 8a6631f1cece ("net: macb: avoid redundant lookup for "mdio" child node in MDIO setup")
Signed-off-by: Nicolai Buchwitz <redacted>
---
 drivers/net/ethernet/cadence/macb_main.c | 2 ++
 1 file changed, 2 insertions(+)

diff --git a/drivers/net/ethernet/cadence/macb_main.c b/drivers/net/ethernet/cadence/macb_main.c
index bba7246e1dbd..b1dc5840d756 100644
--- a/drivers/net/ethernet/cadence/macb_main.c
+++ b/drivers/net/ethernet/cadence/macb_main.c

@@ -1164,6 +1164,8 @@ static int macb_mii_init(struct macb *bp)
 	if (err)
 		goto err_out_unregister_bus;
 
+	of_node_put(mdio_np);
+
 	return 0;
 
 err_out_unregister_bus:

-- 
2.53.0