Fix hearing aid device audio route switch issue.

Currently, audio switching from hearing aid device can't set
audio state in BluetoothRouteManager in proper disconnected state.
Which make the audio route can't switch back to hearing aid device
route since the BluetoothRouteManager don't know the audio route
is disconnected.

Bug: 229358080
Test: atest BluetoothDeviceManagerTest
Merged-In: Id3933942895d9a146e471c39bf0fe69ffe05d0ff
Change-Id: Id3933942895d9a146e471c39bf0fe69ffe05d0ff
(cherry picked from commit 2bbe0da4)