ASoC: tegra: drop Kconfig description for SND_SOC_TEGRA_DAS

The DAS, I2S, and SPDIF Kconfig options are intended to be selected by
the Kconfig options for ASoC machine drivers. As such, they don't need
to be user-visible themselves. Drop the description from the DAS variable
to achieve this. I2S and SPDIF already don't have a description.
Signed-off-by: Stephen Warren <swarren@nvidia.com>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>

sound/soc/tegra/Kconfig

@@ -5,7 +5,7 @@ config SND_SOC_TEGRA
 	  Say Y or M here if you want support for SoC audio on Tegra.
 
 config SND_SOC_TEGRA_DAS
-	tristate "Tegra Digital Audio Switch driver"
+	tristate
 	depends on SND_SOC_TEGRA
 	help
 	  Say Y or M if you want to add support for the Tegra DAS module.