netlink: Remove the dead code in netlink_proto_init()

In the error path of netlink_proto_init(), frees the already allocated
bucket table for new hash tables in a loop, but it is going to panic,
so it is not necessary to clean up the resources, just remove the
dead code.

Suggested-by: Kuniyuki Iwashima <kuniyu@amazon.com>
Signed-off-by: Jinjie Ruan <ruanjinjie@huawei.com>
Link: https://patch.msgid.link/20241030012147.357400-1-ruanjinjie@huawei.com


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