CA-31648: update the VMs' allowed operations after an upgrade.
CA-31648: update the VMs' allowed operations after an upgrade.

Snapshots should now appear in the list of allowed operations after an upgrade.

djs55/xcp-rrdd,sharady/xcp-networkd,johnelse/xcp-rrdd,koushikcgit/xcp-networkd,koushikcgit/xcp-rrdd,simonjbeaumont/xcp-rrdd,koushikcgit/xcp-rrdd,djs55/xcp-networkd,djs55/xcp-rrdd,djs55/squeezed,djs55/xcp-networkd,simonjbeaumont/xcp-rrdd,johnelse/xcp-rrdd,sharady/xcp-networkd,robhoes/squeezed,koushikcgit/xcp-networkd,koushikcgit/xcp-rrdd