BUG/MINOR: quic: Ensure not to retransmit packets with no ack-eliciting frames

Even if there is a check in callers of qc_prep_hdshk_fast_retrans() and
qc_prep_fast_retrans() to prevent retransmissions of packets with no ack-eliciting
frames, these two functions should pay attention not do to that especially if
someone decides to modify their implementations in the future.

Must be backported to 2.6 and 2.7.
1 file changed