Audio : Fix a few minor issues with stream switcher class am: 035beba2 am: f901f6a4

Original change: https://android-review.googlesource.com/c/platform/hardware/interfaces/+/2680756



Change-Id: Idf6d4682688311952a4a04019e971f80595f0e3a
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>