Revert "net: do not leave a dangling sk pointer, when socket creation fails"

This reverts commit 6cd4a78d.

inet/inet6->create() implementations have been fixed to explicitly NULL the
allocated sk object on error.

A warning was put in place to make sure any future changes will not leave
a dangling pointer in pf->create() implementations.

So this code is now redundant.

Suggested-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Ignat Korchagin <ignat@cloudflare.com>
Reviewed-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Reviewed-by: Eric Dumazet <edumazet@google.com>
Link: https://patch.msgid.link/20241014153808.51894-10-ignat@cloudflare.com


Signed-off-by: Jakub Kicinski <kuba@kernel.org>