ASoC: spdif codec: enable use by modules

Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

sound/soc/codecs/spdif_transciever.c

@@ -34,6 +34,7 @@ struct snd_soc_dai dit_stub_dai = {
 		.formats	= STUB_FORMATS,
 	},
 };
+EXPORT_SYMBOL_GPL(dit_stub_dai);
 
 static int spdif_dit_probe(struct platform_device *pdev)
 {