FROMLIST: ASoC: SOF: Add PM support

Add support for saving and restoring DSP context in D3 to host DDR.

Signed-off-by: Liam Girdwood <liam.r.girdwood@linux.intel.com>
(cherry picked from commit 8fa2934d1e60678f2bb2efc2d40f83c0c48ba8c9)
Link:  https://github.com/thesofproject/linux/commit/8fa2934d1e60678f2bb2efc2d40f83c0c48ba8c9


Signed-off-by: Samaga Prasanna Krishna <samaga.krishna@intel.corp-partner.google.com>

BUG=b:110025789
TEST=Test Audio use cases after full SOF series patches are applied.

Change-Id: I164ed9660f6c1587fd7b831b37a07dad7de32678
Reviewed-on: https://chromium-review.googlesource.com/1120595


Commit-Ready: ChromeOS CL Exonerator Bot <chromiumos-cl-exonerator@appspot.gserviceaccount.com>
Tested-by: Curtis Malainey <cujomalainey@chromium.org>
Reviewed-by: Curtis Malainey <cujomalainey@chromium.org>