leaudio: Improve inactivating LeAudio device

with this patch, we notify Audio framework as soon as possible that
LeAudio group is going to be inactive, without waiting for Native to
acknolege group inactivation.

Bug: 242908683
Test: atest BluetoothInstrumentationTests
Tag: #feature
Merged-In: I426f2a933ddc265e1d55fc89eff4f19bed71a119
Change-Id: I426f2a933ddc265e1d55fc89eff4f19bed71a119
(cherry picked from commit 0cb82a29)