Switch the Legacy FT non-voting

This patch makes to stable Zuul CI by switching the Legacy FT
to non-voting because the Legacy API, excluding VIM functionality,
will be deprecated in Antelope release and will not be updated
in the future.

Implements: blueprint deprecate-legacy-apis
Change-Id: Ib28d1f7e01e977b17877efa5df9d5258b10c8e21

.zuul.yaml

@@ -625,11 +625,15 @@
       - release-notes-jobs-python3
     check:
       jobs:
-        - tacker-functional-devstack-multinode-legacy
+        - tacker-functional-devstack-multinode-legacy:
+            # TODO(ueha): Remove the job after Legacy APIs obsolete
+            voting: false
         - tacker-functional-devstack-multinode-sol
         - tacker-functional-devstack-multinode-sol-separated-nfvo
         - tacker-functional-devstack-multinode-sol-kubernetes
-        - tacker-functional-devstack-multinode-libs-master
+        - tacker-functional-devstack-multinode-libs-master:
+            # TODO(ueha): Remove the job after Legacy APIs obsolete
+            voting: false
         - tacker-functional-devstack-multinode-sol-v2
         - tacker-functional-devstack-multinode-sol-separated-nfvo-v2
         - tacker-functional-devstack-multinode-sol-kubernetes-v2