ASoC: rcar: skip disabled-SSI nodes

The current device tree representation of the R-Car SSI assumes that they
are numbered consecutively, starting from 0. Alas, this is not the case
with the R8A77995 (D3) SoC which SSI1/SSI2 aren't present. In order to
keep the existing device trees working, I'm suggesting to use a disabled
node for SSI0/SSI1. Teach the SSI probe to just skip disabled nodes.

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Tested-by: Hiroyuki Yokoyama <hiroyuki.yokoyama.vx@renesas.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/sh/rcar/ssi.c

@@ -1112,6 +1112,9 @@ int rsnd_ssi_probe(struct rsnd_priv *priv)
 
 	i = 0;
 	for_each_child_of_node(node, np) {
+		if (!of_device_is_available(np))
+			goto skip;
+
 		ssi = rsnd_ssi_get(priv, i);
 
 		snprintf(name, RSND_SSI_NAME_SIZE, "%s.%d",
@@ -1148,7 +1151,7 @@ int rsnd_ssi_probe(struct rsnd_priv *priv)
 			of_node_put(np);
 			goto rsnd_ssi_probe_done;
 		}
-
+skip:
 		i++;
 	}