Spurious TCP retries were observed using Wireshark while continuously
sending TCP packets at an interval faster than the initial RTO.
If the send list is empty and CONFIG_NET_TCP_TIME_WAIT_DELAY is used,
the retry timer will not be correctly stopped when receiving a valid
ACK. As a consequence, the timer might be running when a new packet is
queued, but the logics in net_tcp_queue_data() will not restart the
timer as it is already running. This will make the retry timer to expire
prematurely, potentially while sending packets.
The nested condition is merged into a single condition, allowing the
final else clause to be reached when a valid ACK is received.
Signed-off-by: Florian Vaussard <florian.vaussard@gmail.com>
5212659820