tcp: Don't pass hashinfo to socket lookup helpers.

tcp: Don't pass hashinfo to socket lookup helpers.

These socket lookup functions required struct inet_hashinfo because
they are shared by TCP and DCCP.

  * __inet_lookup_established()
  * __inet_lookup_listener()
  * __inet6_lookup_established()
  * inet6_lookup_listener()

DCCP has gone, and we don't need to pass hashinfo down to them.

Let's fetch net->ipv4.tcp_death_row.hashinfo directly in the above
4 functions.

Signed-off-by: Kuniyuki Iwashima <kuniyu@google.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20250822190803.540788-5-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>