tcp: Remove redundant init for req->num_timeout.

tcp: Remove redundant init for req->num_timeout.

Commit 5903123f662e ("tcp: Use BPF timeout setting for SYN ACK
RTO") introduced req->timeout and initialised it in 3 places:

  1. reqsk_alloc() sets 0
  2. inet_reqsk_alloc() sets TCP_TIMEOUT_INIT
  3. tcp_conn_request() sets tcp_timeout_init()

1. has been always redundant as 2. overwrites it immediately.

2. was necessary for TFO SYN+ACK but is no longer needed after
commit 8ea731d4c2ce ("tcp: Make SYN ACK RTO tunable by BPF
programs with TFO").

3. was moved to reqsk_queue_hash_req() in the previous patch.

Now, we always initialise req->timeout just before scheduling
the SYN+ACK timer:

  * For non-TFO SYN+ACK : reqsk_queue_hash_req()
  * For TFO SYN+ACK     : tcp_fastopen_create_child()

Let's remove the redundant initialisation of req->timeout in
reqsk_alloc() and inet_reqsk_alloc().

Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20251106003357.273403-4-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>