[Virtio-fs] [virtiofsd-rs] MR opened: Drop security.capability in setattr() branches

[virtiofs-bot at sinrega.org]

If the security.capability xattr is mapped to something else for the
guest, drop it when executing the uid/gid/trunc branches for setattr.

It must be dropped on all writes and the host kernel won't know to look
for the mapped attribute; only the server knows what the mapped attribute
name is.

Signed-off-by: Connor Kuehl <ckuehl at redhat.com>
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https://gitlab.com/virtio-fs/virtiofsd-rs/-/merge_requests/21