Revert "Add a way to play file descriptor data sources using the A@H transmitter media player."

This reverts commit 64006cb1642b2ec0ee74c66007d869b884391fd1.

Back out this change in order to get ready to implement a longer term,
more media-team approved way of selecting a retransmit player.

Change-Id: I97b68b9859a174eab858598cb00d4445a14fbc17