Buggy value for memory_internal_free on Dom0

[TSnake41]

memory_internal_free is actually reported as bytes but with kilobytes instead.

https://github.com/xapi-project/xen-api/blob/26b6ed61d4edef2699b34eacfb0c901b9edb1b45/ocaml/xcp-rrdd/bin/rrdd/xcp_rrdd.ml

let mem_available () =
  let* size, kb = scan "/proc/meminfo" in
  match kb with "kB" -> ok size | _ -> res_error "unexpected unit: %s" kb

This is read as kilobytes (and is it actually reading the MemAvailable ?)

match mem_available () with
 | Ok mem ->
    Some
     ( Rrd.VM uuid
     , Ds.ds_make ~name:"memory_internal_free" ~units:"B"
    ~description:"Dom0 current free memory"
    ~value:(Rrd.VT_Int64 mem) ~ty:Rrd.Gauge ~min:0.0
    ~default:true ()
    )

But this is pushed as is, with units as "B" instead of "KiB".