configs: Remove Dolby formats by default.

The AC3, EAC3 formats are supported only when
license and respective decoders are present.
Having these entries in policy configuration
by default will unnecessarily trigger
open_output_stream and then fail when
decoders are not present. This results in
glitches at the begining of playback of video
clips with AC3 or EAC3 audio contents.

Removed these entries to make the video playbck
smooth with out any glitches.

CRs-Fixed: 2428579
Change-Id: I41b7ef9d8e2c5f77c261067337f602d705e11c35