ASoC: davinci-mcasp: Symmetric sample bits for IIS mode

In IIS mode the tx and rx configuration is symmetric, the BCLK and FSYNC is
shared.

Signed-off-by: Peter Ujfalusi <peter.ujfalusi@ti.com>
Signed-off-by: Mark Brown <broonie@kernel.org>

sound/soc/davinci/davinci-mcasp.c

@@ -961,6 +961,7 @@ static struct snd_soc_dai_driver davinci_mcasp_dai[] = {
 		},
 		.ops 		= &davinci_mcasp_dai_ops,
 
+		.symmetric_samplebits	= 1,
 	},
 	{
 		.name		= "davinci-mcasp.1",