fix(xo-server/vm.set): setting affinity (#4361)

Caused by 3196c7ca09

Fixes xoa-support#1625

CHANGELOG.unreleased.md

@@ -18,6 +18,7 @@
 > Users must be able to say: “I had this issue, happy to know it's fixed”
 
 - [Task] fix hidden notification by search field [#3874](https://github.com/vatesfr/xen-orchestra/issues/3874) (PR [#4305](https://github.com/vatesfr/xen-orchestra/pull/4305)
+- [VM] Fail to change affinity (PR [#4361](https://github.com/vatesfr/xen-orchestra/pull/4361)
 
 ### Released packages
 

packages/xo-server/src/xapi/mixins/vm.js

@@ -259,7 +259,7 @@ export default {
     affinityHost: {
       get: 'affinity',
       set: (value, vm) =>
-        vm.set_affinity(value ? this.getObject(value).$ref : NULL_REF),
+        vm.set_affinity(value ? vm.$xapi.getObject(value).$ref : NULL_REF),
     },
 
     autoPoweron: {