ASoC: soc-dapm: cleanup cppcheck warning at soc_dapm_dai_stream_event()

This patch cleanups below cppcheck warning.

sound/soc/soc-dapm.c:4368:15: style: The scope of the variable 'ep' can be reduced. [variableScope]
 unsigned int ep;
              ^
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Link: https://lore.kernel.org/r/87im0ku23z.wl-kuninori.morimoto.gx@renesas.comSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/soc-dapm.c

@@ -4365,11 +4365,12 @@ static void soc_dapm_dai_stream_event(struct snd_soc_dai *dai, int stream,
 	int event)
 {
 	struct snd_soc_dapm_widget *w;
-	unsigned int ep;
 
 	w = snd_soc_dai_get_widget(dai, stream);
 
 	if (w) {
+		unsigned int ep;
+
 		dapm_mark_dirty(w, "stream event");
 
 		if (w->id == snd_soc_dapm_dai_in) {