fixes for optional encoder feature "delayed quantization"

The encoder includes an optional feature that can improve the quantization for sample-wise coding modes (can be enabled by setting TrellisQuantDelay > 0). Due to the integartion of some encoder speed-ups, this feature does not work anymore. - This merge request provides a fix, so that the feature can be used again.

Since the feature is turned off in our standard configuration files, there is no impact on coding efficiency for CTC.