[Virtio-fs] [virtiofsd] MR merged: sandbox: Allow non-root users run the daemon without isolation

[virtiofs-bot at sinrega.org]

Although, virtiofsd expect to run as root, either as the real one, or the pseudo-root inside a user namespace, there are use cases there are use cases that need to be able to run virtiofsd as a non-privileged user outside a user namespace.
In this mode many operations will not be available (e.g. chown).

There are some issues that are related to this MR: #8 and #43. Besides the request in #8 recently there was a request for this functionality in the matrix channel, I am creating this MR to have that discussion here.

Notes:

- Some operations fails, like chown, but these also fail with --sandbox=namespace.
- I want to move the capability-related code and `enable_seccomp()` call into `sandbox.rs`, so I don't need to "leak" the info about the sandbox type chosen by the user.
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https://gitlab.com/virtio-fs/virtiofsd/-/merge_requests/136