Fixes for crashes in schema transformer
Fixes for crashes in schema transformer

1. locate_routing_instance could fail if VN itself was deleted. Handle that case.
2. static_route_entries may not be present when route table entry is being deleted.
3. At reinit, use ri name instead of fq_name to find service chain id.

Change-Id: I56524610bc5fe370cb312a6cf633830911cf7e04
Closes-Bug: 1457223

hthompson6/contrail-controller,eonpatapon/contrail-controller,numansiddique/contrail-controller,reiaaoyama/contrail-controller,nischalsheth/contrail-controller,sajuptpm/contrail-controller,codilime/contrail-controller,nischalsheth/contrail-controller,codilime/contrail-controller,reiaaoyama/contrail-controller,eonpatapon/contrail-controller,sajuptpm/contrail-controller,DreamLab/contrail-controller,hthompson6/contrail-controller,hthompson6/contrail-controller,eonpatapon/contrail-controller,DreamLab/contrail-controller,vmahuli/contrail-controller,codilime/contrail-controller,numansiddique/contrail-controller,vmahuli/contrail-controller,DreamLab/contrail-controller,reiaaoyama/contrail-controller,eonpatapon/contrail-controller,reiaaoyama/contrail-controller,rombie/contrail-controller,DreamLab/contrail-controller,codilime/contrail-controller,nischalsheth/contrail-controller,numansiddique/contrail-controller,vpramo/contrail-controller,facetothefate/contrail-controller,vmahuli/contrail-controller,sajuptpm/contrail-controller,nischalsheth/contrail-controller,tcpcloud/contrail-controller,vmahuli/contrail-controller,eonpatapon/contrail-controller,eonpatapon/contrail-controller,rombie/contrail-controller,tcpcloud/contrail-controller,sajuptpm/contrail-controller,facetothefate/contrail-controller,DreamLab/contrail-controller,tcpcloud/contrail-controller,nischalsheth/contrail-controller,codilime/contrail-controller,nischalsheth/contrail-controller,eonpatapon/contrail-controller,numansiddique/contrail-controller,rombie/contrail-controller,rombie/contrail-controller,hthompson6/contrail-controller,reiaaoyama/contrail-controller,sajuptpm/contrail-controller,facetothefate/contrail-controller,facetothefate/contrail-controller,rombie/contrail-controller,numansiddique/contrail-controller,vpramo/contrail-controller,vpramo/contrail-controller,rombie/contrail-controller,vpramo/contrail-controller,tcpcloud/contrail-controller,hthompson6/contrail-controller,sajuptpm/contrail-controller,tcpcloud/contrail-controller,nischalsheth/contrail-controller,rombie/contrail-controller,nischalsheth/contrail-controller,vmahuli/contrail-controller,codilime/contrail-controller,facetothefate/contrail-controller,vpramo/contrail-controller,tcpcloud/contrail-controller