mm-video-v4l2: venc: Squash security fixes

mm-video-v4l2: Avoid buffer access after free buffer call
Change-Id: Ifde8d4e170b8dbeb9f7485d0222b05c3b2a960f3

mm-video-v4l2: venc: Use client allocated memory if available
Change-Id: I45e4f117e98588ee7c888ec5c1cb2424bc7e5fa3

mm-video-v4l2: venc: Avoid buffer access after free
Change-Id: Id439aac54ee64a65ea68b6431a9f5150255a6980

Bugs Fixed: 62452543, 36130225,64750179
CRs-Fixed: 2106434, 2115779
Change-Id: Ifde8d4e170b8dbeb9f7485d0222b05c3b2a960f3
3 files changed