ASoC: soc-card: add snd_soc_card_to_dapm()

Because struct snd_soc_dapm_context is soc-dapm framework specific, user
driver don't need to access its member directly, we would like to hide
them. struct snd_soc_dapm_context will be removed from header in the
future.

Current dapm of card/component are using "instance", but it will be
"pointer" if snd_soc_dapm_context was removed from header.

snd_soc_card_to_dapm() is needed to switch to the new style while
maintaining compatibility

Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Link: https://patch.msgid.link/877byex06i.wl-kuninori.morimoto.gx@renesas.com
Signed-off-by: Mark Brown <broonie@kernel.org>

Author: morimoto

include/sound/soc.h

@@ -1120,6 +1120,11 @@ static inline int snd_soc_card_is_instantiated(struct snd_soc_card *card)
 	return card && card->instantiated;
 }
 
+static inline struct snd_soc_dapm_context *snd_soc_card_to_dapm(struct snd_soc_card *card)
+{
+	return &card->dapm;
+}
+
 /* SoC machine DAI configuration, glues a codec and cpu DAI together */
 struct snd_soc_pcm_runtime {
 	struct device *dev;