[Decode]Optimize function handle when disable hw dec vedio postprocess
[Decode]Optimize function handle when disable hw dec vedio postprocess

When SW decode, MFX_DEC_VIDEO_POSTPROCESS_DISABLE should defined, there is no
SFC usage, should skip this function.

Intel-Media-SDK/MediaSDK,Intel-Media-SDK/MediaSDK,Intel-Media-SDK/MediaSDK,Intel-Media-SDK/MediaSDK,Intel-Media-SDK/MediaSDK