FROMLIST: ASoC: SOF: Add driver debug support.

Add debugFS files that can be used to expose DSP memories and
and peripherals to userspace to assist with firmware debugging.

Signed-off-by: Liam Girdwood <liam.r.girdwood@linux.intel.com>
(cherry picked from commit be725d90d873a56767c96045c29aec594b3bd236)
Link:https://github.com/thesofproject/linux/commit/be725d90d873a56767c96045c29aec594b3bd236


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: I4b108e6f7c835ce42438a6485ed46166ab65755b
Reviewed-on: https://chromium-review.googlesource.com/1120587


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>