[audio][hda] Update HDA driver to use interrupt event sources.

Use new interrupt event sources from dispatcher pool. This removes
what should be the last instance of manually signalling physical
interrupt handles in the system. This should allow for progress on
ZX-2177.

ZX-2177 #comment Last use of manual interrupt signaling removed.
Test: Manual on NUC; ran audio tone test for 24 hrs.

Change-Id: I0c1e0f8f9fe5731b03f0545a7d241f7f0676bf75