cloudstack: Incorrect `memoryintfreekbs` in listVirtualMachines for KVM

The memoryintfreekbs retuned by listVirtualMachines for KVM is always greater than the total memory allocated for the VM. This is because it returns the RSS of the process running the VM (https://libvirt.org/manpages/virsh.html#dommemstat) The RSS shows how much memory is allocated to that process and is in RAM. It is returned by memoryStats over at https://github.com/apache/cloudstack/blob/master/plugins/hypervisors/kvm/src/main/java/com/cloud/hypervisor/kvm/resource/LibvirtComputingResource.java#L3712-L3718 when trying to fetch the free memory instead

Need to discuss how to handle this as well as the impact on usage

ISSUE TYPE

• Bug Report

CLOUDSTACK VERSION

4.11+ (tested)

OS / ENVIRONMENT

KVM

STEPS TO REPRODUCE

(localcloud) SBCM5> > list virtualmachines filter=memory,memoryintfreekbs,memorykbs,memorytargetkbs,
{
  "count": 3,
  "virtualmachine": [
    {
      "memory": 512,
      "memoryintfreekbs": 552836, <---
      "memorykbs": 524288,
      "memorytargetkbs": 524288
    },

EXPECTED RESULTS

The used memory

ACTUAL RESULTS

Total memory used by the process running the VM