APM: support product strategy routing

  Audio policy engine supports receiving a preferred device to use
for a given strategy (Engine superclass). Use of the preferred
device intervenes at the level of the each engine implementation,
here in the default engine in getDevicesForProductStrategy() method
so it is saved in the routing cache, and respects existing routing
priorities.
  Refactor the loops for call and output rerouting into a new
updateCallAndOutputRouting() method.

Bug: 144440677
Test: atest AudioServiceHostTest#testPreferredDeviceRouting

Change-Id: Ic4c690e1b0d8020c4335979e40e14e6df5887879