ASoC: zx296702-i2s: remove unused ‘format’

In zx_i2s_hw_params(), 'format' is initialized and assigned bits based on
params_format, but never used. So remove it.

sound/soc/zte/zx296702-i2s.c: In function ‘zx_i2s_hw_params’:
sound/soc/zte/zx296702-i2s.c:228:21: warning: variable ‘format’ set but not used [-Wunused-but-set-variable]
  unsigned long val, format;
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Acked-by: Jun Nie <jun.nie@linaro.org>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/zte/zx-i2s.c

@@ -225,7 +225,7 @@ static int zx_i2s_hw_params(struct snd_pcm_substream *substream,
 	struct zx_i2s_info *i2s = snd_soc_dai_get_drvdata(socdai);
 	struct snd_dmaengine_dai_dma_data *dma_data;
 	unsigned int lane, ch_num, len, ret = 0;
-	unsigned long val, format;
+	unsigned long val;
 	unsigned long chn_cfg;
 
 	dma_data = snd_soc_dai_get_dma_data(socdai, substream);
@@ -238,15 +238,12 @@ static int zx_i2s_hw_params(struct snd_pcm_substream *substream,
 
 	switch (params_format(params)) {
 	case SNDRV_PCM_FORMAT_S16_LE:
-		format = 0;
 		len = 16;
 		break;
 	case SNDRV_PCM_FORMAT_S24_LE:
-		format = 1;
 		len = 24;
 		break;
 	case SNDRV_PCM_FORMAT_S32_LE:
-		format = 2;
 		len = 32;
 		break;
 	default: