net: enetc: fix device and OF node leak at probe

Make sure to drop the references to the IERB OF node and platform device
taken by of_parse_phandle() and of_find_device_by_node() during probe.

Fixes: e7d48e5f ("net: enetc: add a mini driver for the Integrated Endpoint Register Block")
Cc: stable@vger.kernel.org	# 5.13
Cc: Vladimir Oltean <vladimir.oltean@nxp.com>
Signed-off-by: Johan Hovold <johan@kernel.org>
Reviewed-by: Simon Horman <horms@kernel.org>
Link: https://patch.msgid.link/20250725171213.880-3-johan@kernel.org


Signed-off-by: Jakub Kicinski <kuba@kernel.org>