ASoC: simple-card-utils: support snd_soc_get_dai_id()

ALSA SoC needs to know connected DAI ID for detecting.
It is not a big problem if device/driver was only for sound,
but getting DAI ID will be difficult if device includes both
Video/Sound, like HDMI.
To solve this issue, this patch adds new snd_soc_get_dai_id() and
its related .of_xlate_dai_id callback on component driver.
In below case, we can handle Sound port (= port@2) as ID = 0
if .of_xlate_dai_id has its support.

	hdmi {
		port@0 { /* VIDEO */ };
		port@1 { /* VIDEO */ };
		port@2 { /* SOUND */ };
	};
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/generic/simple-card-utils.c

@@ -177,9 +177,18 @@ static int asoc_simple_card_get_dai_id(struct device_node *ep)
 	struct device_node *node;
 	struct device_node *endpoint;
 	int i, id;
+	int ret;
+
+	ret = snd_soc_get_dai_id(ep);
+	if (ret != -ENOTSUPP)
+		return ret;
 
 	node = of_graph_get_port_parent(ep);
 
+	/*
+	 * Non HDMI sound case, counting port/endpoint on its DT
+	 * is enough. Let's count it.
+	 */
 	i = 0;
 	id = -1;
 	for_each_endpoint_of_node(node, endpoint) {