HfpClientInterface: implement UpdateAudioConfigToHal

This CL implements the function that allows updating audio config
(specifically, to account for codec change in HFP) for SW path.

Test: m com.google.android.btservices
Bug: 349290628
Bug: 315234036
Flag: com::android::bluetooth::flags::is_sco_managed_by_audio and HFP
and bluetooth.hfp.software_datapath.enabled

Change-Id: I801f5baabc5fef9081650336a52a194b3235de0e