Fix type confusion in avdt_msg.cc am: 359bdee1 am: bb16cfa4 am: 2ab2b244 am: 76085bc1

Original change: https://googleplex-android-review.googlesource.com/c/platform/packages/modules/Bluetooth/+/29817244



Change-Id: Ie9ef0032dbf369bc60822e2137701495e7c8f85e
Signed-off-by: Automerger Merge Worker <android-build-automerger-merge-worker@system.gserviceaccount.com>