ASoC: Intel: remove misleading DMA error messages on Baytrail platforms

During probe, the Baytrail audio driver reports errors such as:

[44.172040] baytrail-pcm-audio baytrail-pcm-audio: error: invalid DMA engine 0
[44.172137] baytrail-pcm-audio baytrail-pcm-audio: sst_dma_new failed

Those error messages are misleading, there is no error since the DMA
is explicitly not configured for Baytrail.
Add a test to remove DMA error checks when DMA is not configured
and return silently.

Acked-by: Liam Girdwood <liam.r.girdwood@linux.intel.com>
Signed-off-by: Pierre-Louis Bossart <pierre-louis.bossart@linux.intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>
diff --git a/sound/soc/intel/sst-acpi.c b/sound/soc/intel/sst-acpi.c
index b3d8456..42f293f 100644
--- a/sound/soc/intel/sst-acpi.c
+++ b/sound/soc/intel/sst-acpi.c
@@ -142,6 +142,7 @@
 	sst_acpi->desc = desc;
 	sst_acpi->mach = mach;
 
+	sst_pdata->resindex_dma_base = desc->resindex_dma_base;
 	if (desc->resindex_dma_base >= 0) {
 		sst_pdata->dma_engine = desc->dma_engine;
 		sst_pdata->dma_base = desc->resindex_dma_base;