ring/contrib: remove CCRTP/UCOMMON/ZRTPCPP deps

This patch have the side effect to refactor audio
and video related parts by moving them into media
sub-directory and making libav common parts
undependent of video.
This patch permits to disable video without
loosing libav support on audio.

Refs #63906

Change-Id: I3d50713fac7f5c2738cc68b9f38573b5b4536b35