tcp: adjust rto_base in retransmits_timed_out()

The cited commit exposed an old retransmits_timed_out() bug
which assumed it could call tcp_model_timeout() with
TCP_RTO_MIN as rto_base for all states.

But flows in SYN_SENT or SYN_RECV state uses a different
RTO base (1 sec instead of 200 ms, unless BPF choses
another value).

This caused a reduction of SYN retransmits from 6 to 4 with
the default /proc/sys/net/ipv4/tcp_syn_retries value.

Change-Id: I424b7a716ceee8d455701f6470b0688e1fa1dc5a
Fixes: a41e8a88b06e ("tcp: better handle TCP_USER_TIMEOUT in SYN_SENT state")
Signed-off-by: Eric Dumazet <edumazet@google.com>
Cc: Yuchung Cheng <ycheng@google.com>
Cc: Marek Majkowski <marek@cloudflare.com>
Git-Commit: 3256a2d6ab1f71f9a1bd2d7f6f18eb8108c48d17
Git-repo: https://android.googlesource.com/kernel/common/


Signed-off-by: Kaustubh Pandey <kapandey@codeaurora.org>