mm-video-v4l2: vdec: add frame QP request as extra data

Provides frame level QP information. For H264 it is the slice level QP
averaged over whole frame. For all other codecs its frame level QP.
To get the extra data use the standard OpenMAX IL for custom indexes:
Request the index value using: "OMX.QCOM.index.param.video.QPExtradata"
Or directly using the index OMX_QcomIndexParamVideoQPExtraData

Change-Id: Id36820d4b62c7c582c41b72b5811e56d58d2038e
3 files changed