Ensure switchVolumeDevice() be called

When volumeDeviceSwitched() called after deviceConnected(),
switchVolumeDevice() is not called.
This CL ensures switchVolumeDevice() is called in that case.

Bug: 261887806
Test: atest BluetoothInstrumentationTests:AvrcpVolumeManagerTest
Change-Id: I12eba0e0e8cee84e279d0f51f31cebfa7cba5e9e