Merge commit '9c1e111406bd4cbb04d8e8611b71bebf203bec5e'

* commit '9c1e111406bd4cbb04d8e8611b71bebf203bec5e':
  flac: Convert to the new bitstream reader
  bitstream: Avoid undefined behavior in bitstream_skip()

This commit is a noop, see
https://ffmpeg.org/pipermail/ffmpeg-devel/2017-April/209609.html

Merged-by: James Almer <jamrial@gmail.com>