video: driver: skip lazy unmap for dec output buffers

- add support to skip lazy unmapping for decoder
  output buffers only. Map twice for these buffers.
- v4l2 client owned RO SMMU mapped buffers are
  maintained separately in read_only list.
- For FBD with RO flag from fw, add buffer to read_only
  list. Else remove from this list.
- During FTB, if buffer present in read_only list,
  add RO flag to hfi buffer and queue to fw.
- During streamoff output, unmap all buffers except
  those present in read_only list.
- During close, unmap completely and clean up read_only
  list, output list.

Change-Id: Iacee7d298dfbff0b9cb6f17dff27ad98574b489b
Signed-off-by: Darshana Patil <darshana@codeaurora.org>

driver/vidc/inc/msm_vidc_inst.h

@@ -56,6 +56,7 @@ struct msm_vidc_mappings_info {
 struct msm_vidc_buffers_info {
 	struct msm_vidc_buffers        input;
 	struct msm_vidc_buffers        output;
+	struct msm_vidc_buffers        read_only;
 	struct msm_vidc_buffers        input_meta;
 	struct msm_vidc_buffers        output_meta;
 	struct msm_vidc_buffers        bin;