Revert "audio: Use hardcoded r_submix configuration with XML" am: 567d0de485 am: a37a4feed2

Original change: https://android-review.googlesource.com/c/platform/hardware/interfaces/+/2786754

Change-Id: Ic0c09527c9284811ada3c1b28adb2431b43ebadc
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>