ASoC: Intel: Skylake: Move sst common initialization to a helper function

ASoC: Intel: Skylake: Move sst common initialization to a helper function

Some skl sst context are not dependent of platform and initializing them
independently for each platform can lead to errors. So optimize by
moving them to a helper function and platform specific init code can
call this.

Signed-off-by: G Kranthi <gudishax.kranthikumar@intel.com>
Signed-off-by: Subhransu S. Prusty <subhransu.s.prusty@intel.com>
Acked-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>