Not start code and slice_data_offset for H.264(AVC) VASliceDataBufferType type data

Submitted by Randy Li (ayaka)

Assigned to Randy Li (ayaka)

Link to original bug (#770683)

Description

The Intel i915 VA-API doesn't require the start code for H.264(AVS) but the HEVC does, it would use the slice_data_offset to omit the start code prefix(0x000001). But some hardware video process do require the start code for AVS. The known device are those ARM chips from rockchips.

It would be not strip the start code for AVS to work in all the devices.