ASoC: Remove export of snd_soc_dapm_stream_event()

The only thing that should ever be calling this is soc-core and that is
built as part of the same module so doesn't need the export.
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>

sound/soc/soc-dapm.c

@@ -2263,7 +2263,6 @@ int snd_soc_dapm_stream_event(struct snd_soc_pcm_runtime *rtd,
 	mutex_unlock(&codec->mutex);
 	return 0;
 }
-EXPORT_SYMBOL_GPL(snd_soc_dapm_stream_event);
 
 /**
  * snd_soc_dapm_enable_pin - enable pin.