media: firewire: fix memory leak

Fix memory leak in node_probe.

Signed-off-by: Pavel Machek (CIP) <pavel@denx.de>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>
Signed-off-by: Mauro Carvalho Chehab <mchehab+huawei@kernel.org>