ASoC: pcm: make soc_dpcm_runtime_update() accessible from modules

the soc_dpcm_runtime_update() method will be called to establish a
connection to the BE and enable the codec. So make this method
accessible to modules.

Signed-off-by: Ranjani Sridharan <ranjani.sridharan@linux.intel.com>

sound/soc/soc-pcm.c

@@ -2758,6 +2758,8 @@ int soc_dpcm_runtime_update(struct snd_soc_card *card)
 	mutex_unlock(&card->mutex);
 	return 0;
 }
+EXPORT_SYMBOL_GPL(soc_dpcm_runtime_update);
+
 int soc_dpcm_be_digital_mute(struct snd_soc_pcm_runtime *fe, int mute)
 {
 	struct snd_soc_dpcm *dpcm;