Use stop() method on MessageHandlingServer
Use stop() method on MessageHandlingServer

MessageHandlingServer has no kill() method. In case neutron server using
rpc workers and is stopped, wrong method is called.

Change-Id: Id4a11f3dca070e684fb9e079139ac09792bc7aad
Closes-Bug: 1387053
(cherry picked from commit 42f4c8d0e693a7ef8b058111f5e1bf1ecc618620)

cernops/neutron,cernops/neutron,redhat-openstack/neutron,redhat-openstack/neutron