MINOR: quic: Send packets as much as possible from qc_send_app_pkts()

Add a loop into this function to send more packets from this function
which is called by the mux. It is broken when we could not prepare
packet with qc_prep_app_pkts() due to missing available room in the
buffer used to send packets. This improves the throughput.

Must be backported to 2.6.
1 file changed