ASoC: amd: raven: acp3x-pcm-dma: fix 'set but not used' warning

Fix W=1 warning. the card variable is useless here.
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Link: https://lore.kernel.org/r/20200702164433.162815-4-pierre-louis.bossart@linux.intel.comSigned-off-by: Mark Brown <broonie@kernel.org>

sound/soc/amd/raven/acp3x-pcm-dma.c

@@ -302,14 +302,12 @@ static snd_pcm_uframes_t acp3x_dma_pointer(struct snd_soc_component *component,
 					   struct snd_pcm_substream *substream)
 {
 	struct snd_soc_pcm_runtime *prtd;
-	struct snd_soc_card *card;
 	struct i2s_stream_instance *rtd;
 	u32 pos;
 	u32 buffersize;
 	u64 bytescount;
 
 	prtd = substream->private_data;
-	card = prtd->card;
 	rtd = substream->runtime->private_data;
 
 	buffersize = frames_to_bytes(substream->runtime,