ASoC: audio-graph-card2: call of_node_get() before of_get_next_child()

ASoC: audio-graph-card2: call of_node_get() before of_get_next_child()

commit c6f597bc598a8 ("ASoC: audio-graph-card2: remove unneeded
of_node_get()") removed of_node_get(), but it need to keep original
reference, so of_node_get() itself is needed.

Because of_get_next_child() will call of_node_put() inside, if the
reference count dropped to zero, then of_node_get() after that will be
use afer free. Need to call of_node_get() *before* that.

Fixes: c6f597bc598a ("ASoC: audio-graph-card2: remove unneeded of_node_get()")
Link: https://lore.kernel.org/r/f930862e-9d30-4ea3-b3e7-b4b4f411f6d1@moroto.mountain
Reported-by: Dan Carpenter <dan.carpenter@linaro.org>
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Link: https://lore.kernel.org/r/875xvmqzs8.wl-kuninori.morimoto.gx@renesas.com
Signed-off-by: Mark Brown <broonie@kernel.org>