ASoC: soc-generic-dmaengine-pcm: cleanup cppcheck warning at dmaengine_copy_user()

This patch cleanups below cppcheck warning.

sound/soc/soc-generic-dmaengine-pcm.c:310:6: style: The scope of the variable 'ret' can be reduced. [variableScope]
 int ret;
     ^
Signed-off-by: Kuninori Morimoto <kuninori.morimoto.gx@renesas.com>
Link: https://lore.kernel.org/r/87zgtiyomb.wl-kuninori.morimoto.gx@renesas.comSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/soc-generic-dmaengine-pcm.c

@@ -305,14 +305,13 @@ static int dmaengine_copy_user(struct snd_soc_component *component,
 	bool is_playback = substream->stream == SNDRV_PCM_STREAM_PLAYBACK;
 	void *dma_ptr = runtime->dma_area + hwoff +
 			channel * (runtime->dma_bytes / runtime->channels);
-	int ret;
 
 	if (is_playback)
 		if (copy_from_user(dma_ptr, buf, bytes))
 			return -EFAULT;
 
 	if (process) {
-		ret = process(substream, channel, hwoff, (__force void *)buf, bytes);
+		int ret = process(substream, channel, hwoff, (__force void *)buf, bytes);
 		if (ret < 0)
 			return ret;
 	}