media: c8sectpfe: Add of_node_put() when breaking out of loop

In configure_channels(), we should call of_node_put() when breaking
out of for_each_child_of_node() which will automatically increase
and decrease the refcount.

Fixes: c5f5d0f9 ("[media] c8sectpfe: STiH407/10 Linux DVB demux support")
Signed-off-by: Liang He <windhl@126.com>
Signed-off-by: Hans Verkuil <hverkuil-cisco@xs4all.nl>