Dialer: Fix Voicemail playback

* With the AndroidX conversion, onActivityCreated gets called later than
  the only call to getVoicemailPlaybackPresenter(), which in turn
  returns null and thus leading to hiding the playback controls
* Split the deprecated method into the ones we need: onCreate() for
  non-UI initialisations and onViewCreated for the others

Fixes: https://gitlab.com/LineageOS/issues/android/-/issues/6667
Change-Id: I0da4a9114a80e62fd25138ce9c92e9fb7f386d53