xenops: Fix migrate parameter ordering (#6823)

localhost_migration was introduced as the last parameter for migrate in
xenops_interface.ml, but was second to last in xenops_server.ml.

This meant that non-localhost migrations with verify_dest=true were
classed as localhost and did not balloon down before migration.

Fixes: 0911604 ("xenopsd: Don't balloon down memory on same-host
migration")

Author: last-genius

ocaml/xenopsd/lib/xenops_server.ml

@@ -3842,7 +3842,7 @@ module VM = struct
   let s3resume _ dbg id = queue_operation dbg id (Atomic (VM_s3resume id))
 
   let migrate _context dbg id vmm_vdi_map vmm_vif_map vmm_vgpu_pci_map vmm_url
-      (compress : bool) (localhost_migration : bool) (verify_dest : bool) =
+      (compress : bool) (verify_dest : bool) (localhost_migration : bool) =
     let tmp_uuid_of uuid ~kind =
       Printf.sprintf "%s00000000000%c" (String.sub uuid 0 24)
         (match kind with `dest -> '1' | `src -> '0')