remove unneeded call to network_api on rebuild_instance
remove unneeded call to network_api on rebuild_instance

When rebuilding an instance we call the network_api and which results in
calling neutron and updating the info cache. We do not actually need to
do this as we can get the nw_info directly from the instance's info cache.

Change-Id: I2bcc2f15b1e5bb52d972098c7bc3e12f160b6feb
Closes-bug: 1294914

tudorvio/nova,alexandrucoman/vbox-nova-driver,petrutlucian94/nova,cloudbase/nova-virtualbox,JianyuWang/nova,jianghuaw/nova,mmnelemane/nova,zaina/nova,ted-gould/nova,phenoxim/nova,rahulunair/nova,bgxavier/nova,angdraug/nova,kimjaejoong/nova,cernops/nova,tudorvio/nova,sebrandon1/nova,Yusuke1987/openstack_template,viggates/nova,berrange/nova,eayunstack/nova,badock/nova,tianweizhang/nova,belmiromoreira/nova,felixma/nova,eonpatapon/nova,tianweizhang/nova,sebrandon1/nova,gooddata/openstack-nova,badock/nova,adelina-t/nova,virtualopensystems/nova,hanlind/nova,dawnpower/nova,JioCloud/nova_test_latest,BeyondTheClouds/nova,barnsnake351/nova,alvarolopez/nova,alexandrucoman/vbox-nova-driver,takeshineshiro/nova,hanlind/nova,saleemjaveds/https-github.com-openstack-nova,maelnor/nova,thomasem/nova,bgxavier/nova,Tehsmash/nova,cyx1231st/nova,devendermishrajio/nova_test_latest,cloudbase/nova,shail2810/nova,akash1808/nova,cernops/nova,j-carpentier/nova,noironetworks/nova,joker946/nova,Stavitsky/nova,MountainWei/nova,jianghuaw/nova,devendermishrajio/nova,yosshy/nova,rahulunair/nova,tealover/nova,JioCloud/nova,zhimin711/nova,mgagne/nova,fnordahl/nova,mikalstill/nova,Yusuke1987/openstack_template,CiscoSystems/nova,yatinkumbhare/openstack-nova,phenoxim/nova,klmitch/nova,NeCTAR-RC/nova,thomasem/nova,eayunstack/nova,mikalstill/nova,apporc/nova,tangfeixiong/nova,scripnichenko/nova,dims/nova,hanlind/nova,projectcalico/calico-nova,virtualopensystems/nova,BeyondTheClouds/nova,vmturbo/nova,shail2810/nova,vmturbo/nova,akash1808/nova,tangfeixiong/nova,JioCloud/nova,joker946/nova,Francis-Liu/animated-broccoli,j-carpentier/nova,mikalstill/nova,CEG-FYP-OpenStack/scheduler,yosshy/nova,sebrandon1/nova,dims/nova,gooddata/openstack-nova,angdraug/nova,silenceli/nova,orbitfp7/nova,cloudbase/nova,jeffrey4l/nova,MountainWei/nova,mahak/nova,redhat-openstack/nova,jianghuaw/nova,whitepages/nova,affo/nova,fnordahl/nova,gooddata/openstack-nova,alaski/nova,belmiromoreira/nova,watonyweng/nova,vladikr/nova_drafts,orbitfp7/nova,affo/nova,JianyuWang/nova,mahak/nova,Metaswitch/calico-nova,tealover/nova,openstack/nova,LoHChina/nova,devendermishrajio/nova_test_latest,klmitch/nova,isyippee/nova,devendermishrajio/nova,adelina-t/nova,klmitch/nova,silenceli/nova,berrange/nova,rajalokan/nova,BeyondTheClouds/nova,openstack/nova,vladikr/nova_drafts,LoHChina/nova,noironetworks/nova,iuliat/nova,TwinkleChawla/nova,blueboxgroup/nova,Tehsmash/nova,mgagne/nova,ruslanloman/nova,kimjaejoong/nova,viggates/nova,mandeepdhami/nova,varunarya10/nova_test_latest,CloudServer/nova,vmturbo/nova,petrutlucian94/nova,CloudServer/nova,takeshineshiro/nova,scripnichenko/nova,mandeepdhami/nova,double12gzh/nova,rajalokan/nova,akash1808/nova_test_latest,cloudbase/nova-virtualbox,raildo/nova,jianghuaw/nova,whitepages/nova,isyippee/nova,Juniper/nova,projectcalico/calico-nova,vmturbo/nova,blueboxgroup/nova,ruslanloman/nova,Juniper/nova,Juniper/nova,tanglei528/nova,ted-gould/nova,NeCTAR-RC/nova,dawnpower/nova,raildo/nova,tanglei528/nova,yatinkumbhare/openstack-nova,Juniper/nova,TwinkleChawla/nova,iuliat/nova,mahak/nova,CEG-FYP-OpenStack/scheduler,bigswitch/nova,zhimin711/nova,zaina/nova,Metaswitch/calico-nova,rahulunair/nova,cloudbase/nova,akash1808/nova_test_latest,mmnelemane/nova,rajalokan/nova,redhat-openstack/nova,CCI-MOC/nova,zzicewind/nova,apporc/nova,bigswitch/nova,Francis-Liu/animated-broccoli,openstack/nova,rajalokan/nova,zzicewind/nova,JioCloud/nova_test_latest,felixma/nova,nikesh-mahalka/nova,barnsnake351/nova,CCI-MOC/nova,watonyweng/nova,Stavitsky/nova,edulramirez/nova,eonpatapon/nova,varunarya10/nova_test_latest,cyx1231st/nova,saleemjaveds/https-github.com-openstack-nova,klmitch/nova,double12gzh/nova,gooddata/openstack-nova,nikesh-mahalka/nova,alvarolopez/nova,cernops/nova,edulramirez/nova,CiscoSystems/nova,jeffrey4l/nova,alaski/nova,maelnor/nova