netfilter: nft_socket: remove WARN_ON_ONCE on maximum cgroup level

netfilter: nft_socket: remove WARN_ON_ONCE on maximum cgroup level

[ Upstream commit b7529880cb961d515642ce63f9d7570869bbbdc3 ]

cgroup maximum depth is INT_MAX by default, there is a cgroup toggle to
restrict this maximum depth to a more reasonable value not to harm
performance. Remove unnecessary WARN_ON_ONCE which is reachable from
userspace.

Fixes: 7f3287db6543 ("netfilter: nft_socket: make cgroupsv2 matching work with namespaces")
Reported-by: syzbot+57bac0866ddd99fe47c0@syzkaller.appspotmail.com
Signed-off-by: Pablo Neira Ayuso <pablo@netfilter.org>
Signed-off-by: Sasha Levin <sashal@kernel.org>