[FFmpeg-devel] version 3: V4L2 M2M codecs

[Jorge Ramirez-Ortiz]

The following patchset adds support for V4L2 mem2mem codecs.

This feature gives ffmpeg access to any hardware codec implementing the
V4L2 API. Since the number of hardware codecs implementing this API is
expected to increase, we believe it will be benefitial to all users to
integrate its support in the ffmpeg project.

These patches were originally posted by Alexis Ballier back in 2014
and since then they have been reviewed and tested further in different
platforms.

v2 -> v3:
   rebased on ffmpeg/master [1193301758]
   fixes make install
   renames v4l2_* files 

* [PATCHv3 1/4] Move lavd/v4l2-common.* to lavc
* [PATCHv3 2/4] libavcodec: v4l2: add pack_flags to the conversion tables
* [PATCHv3 3/4] libavcodec: v4l2: add codec formats

* [PATCHv3 4/4] libavcodec: v4l2: add support for v4l2 mem2mem codecs
 compat/v4l2/v4l2-common.h                |  107 ++++++++++++
 compat/v4l2/v4l2-controls.h              |  987 +++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 compat/v4l2/videodev2.h                  | 2402 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 configure                                |   26 ++-
 libavcodec/Makefile                      |   18 +-
 libavcodec/allcodecs.c                   |    9 +
 libavcodec/v4l2_buffers.c                |  614 ++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++++
 libavcodec/v4l2_buffers.h                |  226 +++++++++++++++++++++++++
 libavcodec/{v4l2-common.c => v4l2_fmt.c} |   56 ++++---
 libavcodec/{v4l2-common.h => v4l2_fmt.h} |    8 +-
 libavcodec/v4l2_m2m.c                    |  356 ++++++++++++++++++++++++++++++++++++++++
 libavcodec/v4l2_m2m.h                    |   69 ++++++++
 libavcodec/v4l2_m2m_avcodec.h            |   32 ++++
 libavcodec/v4l2_m2m_dec.c                |  229 ++++++++++++++++++++++++++
 libavcodec/v4l2_m2m_enc.c                |  270 ++++++++++++++++++++++++++++++
 libavdevice/v4l2.c                       |    2 +-
 libavdevice/v4l2enc.c                    |    2 +