[Rootless] Unsound nydus-snapshotter crash with rootless + cgroup enabled

[inklesspen1rus]

Tried to user nydus-snapshotter from rootless user but got unsound crash:

$ /usr/local/bin/containerd-nydus-grpc --config /home/inklesspen/.config/nydus/config.toml
$ echo $?
1
$

I got that until disabled cgroup in /home/inklesspen/.config/nydus/config.toml

Is that good idea to add some error messages on crashes?

[imeoer]

We haven't tried running nydus snapshotter in rootless, maybe we can try adding some logs to the snapshot/snapshot.go -> NewSnapshotter code to debug, thanks!