Treblize audio policy xml config file location

Treblization requires to locate partner-specific configs in its own
partition. So the audio policy xml config file could be located in
/odm/etc or /vendor/etc.
This CL is to support those locations for the config.

Test: building succeeded and tested on sailfish.
Bug: 35369237
Change-Id: Ie59db630456f7690bbeca08017bea8b174651394