Fix audio_engine API for 4.3

These methods are likely to be needed and accessible through other
means, so keep them around until the updated API is actually read

Change-Id: Icba0e95f3f293279f260df92e6bd6b1aea5ed7bc
DSPManager: grammar correction

https://jira.cyanogenmod.org/browse/CYAN-1873

Change-Id: Icf06220def1b04b2ab077c103d5ad3e7db2f5d1b