ASoC: Intel: Add dependency on DesignWare DMA controller

We have calls into the controller so we need to ensure it is being
built.

Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/sound/soc/intel/Kconfig b/sound/soc/intel/Kconfig
index 2a3af88..ae7f872 100644
--- a/sound/soc/intel/Kconfig
+++ b/sound/soc/intel/Kconfig
@@ -20,6 +20,7 @@
 	tristate "ASoC support for Intel(R) Smart Sound Technology"
 	select SND_SOC_INTEL_SST_ACPI if ACPI
 	depends on (X86 || COMPILE_TEST)
+	depends on DW_DMAC_CORE
 	help
           This adds support for Intel(R) Smart Sound Technology (SST).
           Say Y if you have such a device