Fixed resource leakage while SNAT cleanup
Fixed resource leakage while SNAT cleanup

Change-Id: Ida8082da1a43a41df34337314d35466300421461
Closes-bug: #1493266

rombie/contrail-controller,vmahuli/contrail-controller,numansiddique/contrail-controller,numansiddique/contrail-controller,vmahuli/contrail-controller,sajuptpm/contrail-controller,sajuptpm/contrail-controller,nischalsheth/contrail-controller,tcpcloud/contrail-controller,nischalsheth/contrail-controller,rombie/contrail-controller,nischalsheth/contrail-controller,codilime/contrail-controller,vmahuli/contrail-controller,eonpatapon/contrail-controller,numansiddique/contrail-controller,codilime/contrail-controller,rombie/contrail-controller,nischalsheth/contrail-controller,numansiddique/contrail-controller,nischalsheth/contrail-controller,eonpatapon/contrail-controller,sajuptpm/contrail-controller,eonpatapon/contrail-controller,sajuptpm/contrail-controller,tcpcloud/contrail-controller,eonpatapon/contrail-controller,nischalsheth/contrail-controller,sajuptpm/contrail-controller,rombie/contrail-controller,eonpatapon/contrail-controller,tcpcloud/contrail-controller,codilime/contrail-controller,sajuptpm/contrail-controller,tcpcloud/contrail-controller,eonpatapon/contrail-controller,rombie/contrail-controller,vmahuli/contrail-controller,numansiddique/contrail-controller,codilime/contrail-controller,tcpcloud/contrail-controller,codilime/contrail-controller,nischalsheth/contrail-controller,vmahuli/contrail-controller,codilime/contrail-controller,tcpcloud/contrail-controller,rombie/contrail-controller,rombie/contrail-controller,eonpatapon/contrail-controller,nischalsheth/contrail-controller