[sample_decode] Remove unnecessary shift settings
[sample_decode] Remove unnecessary shift settings

After commit 757ea7 we dont need this shift setting,
because it's already filled in mfxVideoParams by
DecodeHeader.

Fixes #1988

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