ASoC: sst_platform porting sst dsp driver interface as per latest in Greg's staging tree

The interface between sst platform driver and intel sst dsp driver
have been changed in Greg's staging tree - next branch

This patch adds the interface changes compatible with the new interface
in Greg's staging tree

Signed-off-by: Harsha Priya <priya.harsha@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Acked-by: Liam Girdwood <lrg@slimlogic.co.uk>
Signed-off-by: Mark Brown <broonie@opensource.wolfsonmicro.com>