Fix possible race on saving NodeID
Fix possible race on saving NodeID

Signed-off-by: Tonis Tiigi <c2470c48b2d3312d61f94f18d3a1cd113d1915ad@gmail.com>
AliyunContainerService/swarmkit,allencloud/swarmkit,docker/swarmkit,Noyan759/swarmkit,runshenzhu/swarmkit,sungwonh/swarmkit,fate-grand-order/swarmkit,sungwonh/swarmkit,yp-engineering/swarmkit,allencloud/swarmkit,dperny/swarmkit-1,jlhawn/swarmkit,alyyousuf7/swarmkit,diogomonica/swarmkit,AliyunContainerService/swarmkit,aaronlehmann/swarmkit,dperny/swarmkit-1,aaronlehmann/swarmkit,docker/swarmkit,diogomonica/swarmkit,elifa/swarmkit,vasil-yordanov/swarmkit,jlhawn/swarmkit,Noyan759/swarmkit,cheyang/swarmkit,yongtang/swarmkit,vasil-yordanov/swarmkit,elifa/swarmkit,deljuven/swarmkit,yp-engineering/swarmkit,fate-grand-order/swarmkit,RenaudWasTaken/swarmkit,yongtang/swarmkit,cheyang/swarmkit,runshenzhu/swarmkit,alyyousuf7/swarmkit,cezarsa/swarmkit,deljuven/swarmkit,cezarsa/swarmkit,RenaudWasTaken/swarmkit