Merge branch 'tcp-clean-up-inet_hash-and-inet_unhash'

Kuniyuki Iwashima says:

====================
tcp: Clean up inet_hash() and inet_unhash().

While reviewing the ehash fix series from Xuanqiang Luo [0],
I noticed that inet_twsk_hashdance_schedule() checks the
retval of __sk_nulls_del_node_init_rcu(), which looks confusing.

The test exists from the pre-git era:

  $ git blame -L:tcp_tw_hashdance net/ipv4/tcp_minisocks.c e48c414ee61f4~

Patch 3 is to clarify that the retval check is unnecessary in
inet_twsk_hashdance_schedule(), but I'll delegate its removal
to the Xuanqiang's series.

Patch 1 & 2 are minor cleanups.

[0]: https://lore.kernel.org/netdev/20250916103054.719584-4-xuanqiang.luo@linux.dev/
====================

Link: https://patch.msgid.link/20250919083706.1863217-1-kuniyu@google.com
Signed-off-by: Jakub Kicinski <kuba@kernel.org>