ASoC: Intel: Skylake: Fix PM behaviour

The driver runtime behaviour is fine but in suspend, we missed
setting the DSP to suspend and also missed resuming DSP on
resume.

Fix this by having common SKL suspend and resume routines which
power up/down links, suspend/resume DSP and other common
routines, and call these routines from both runtime as well as
system PM handlers

Signed-off-by: Jayachandran B <jayachandran.b@intel.com>
Signed-off-by: Jeeja KP <jeeja.kp@intel.com>
Signed-off-by: Vinod Koul <vinod.koul@intel.com>
Signed-off-by: Mark Brown <broonie@kernel.org>