g3dvl: Rework the decoder interface part 2/5

Implement PIPE_CAP_NUM_BUFFERS_DESIRED giving the decoder control over
the number of buffers a state tracker should allocate.

Signed-off-by: Christian König <deathsimple@vodafone.de>
Reviewed-by: Younes Manton <younes.m@gmail.com>
10 files changed