DLS: fix loop calculation for 16-bit am: 97f70ed81d

Original change: https://googleplex-android-review.googlesource.com/c/platform/external/sonivox/+/18349826

Change-Id: I626a4ac639ea9449d125b37cc14ebd87932a6d27
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>