ASoC: Add component pointer to the DAI struct

Keep track of which component registered a DAI. We'll need this as
componentization progresses.

Signed-off-by: Lars-Peter Clausen <lars@metafoo.de>
Signed-off-by: Mark Brown <broonie@linaro.org>

include/sound/soc-dai.h

@@ -270,6 +270,7 @@ struct snd_soc_dai {
 	/* parent platform/codec */
 	struct snd_soc_platform *platform;
 	struct snd_soc_codec *codec;
+	struct snd_soc_component *component;
 
 	struct snd_soc_card *card;