msm: vidc: Decouple extradata plane from RBR handling

Manage RBR list add/look-up/deletion based on the image
plane only. This allows the client to associate different
extradata buffer when re-queueing the same output buffer.
Unmap and cleanup extradata plane as soon as the firmware
emits the output (Since it will no longer be referenced).

Test:
  playback all formats with OMX
  playback all formats with Codec2.0

Change-Id: Id251184502af692063150a4c66d49ee7ea5529c4
Signed-off-by: Praveen Chavan <pchavan@codeaurora.org>