Fix AAudio builder requested device id during stream open

[robertwu1]

The recent routing changed callback patch overrode getDeviceId() in
AudioStreamAAudio to dynamically return the mUpdatedDeviceIds array.

However, this caused a critical initialization bug.

During stream creation in AudioStreamAAudio::open(), the builder was
configured via builder_setDeviceId(aaudioBuilder, getDeviceId()). Because
mUpdatedDeviceIds is unpopulated until the very end of the open()
sequence, getDeviceId() evaluated to an empty array and prematurely
returned 0 (kUnspecified).

As a result, Oboe was completely ignoring the app's requested device
ID and strictly routing to the default microphone and speaker.
This explicitly queries AudioStreamBase::getDeviceId() during builder
initialization to correctly retrieve the app's originally requested
device ID, avoiding the overridden dynamic routing array.

[flamme]

Thanks for the excellent debugging and fast fix!