ASoC: rsnd: rsrc-card: check return value of snd_soc_of_get_dai_name()

This patch adds missing check of snd_soc_of_get_dai_name().
It might not be able to use sound card, because it might returns
-EPROBE_DEFER.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>