3fe3251593
The previous commit was a major rework for QUIC MUX sending process. Following this, this patch cleans up a few elements that remains but can be removed as they are duplicated. Of notable changes, offset fields from QCS and QCC are removed. They are both equivalent to flow control soft offsets. A new function qcs_prep_bytes() is implemented. Its purpose is to return the count of prepared data bytes not yet sent. It also replaces qcs_need_sending().