Use state transition checker wait function in the ec2 image tests
Use state transition checker wait function in the ec2 image tests

Now the test_register_get_deregister_ami_image can use the usual
transition checker wait logic.
Previously the bug 1074904 prevented it.

Change-Id: I75d90c92aaa50dc62f15a962a5f14ba395b2948c

citrix-openstack-build/tempest,bigswitch/tempest,eggmaster/tempest,afaheem88/tempest_neutron,Tesora/tesora-tempest,Vaidyanath/tempest,flyingfish007/tempest,armando-migliaccio/tempest,izadorozhna/tempest,flyingfish007/tempest,izadorozhna/tempest,adkerr/tempest,BeenzSyed/tempest,queria/my-tempest,LIS/lis-tempest,BeenzSyed/tempest,neerja28/Tempest,citrix-openstack-build/tempest,manasi24/jiocloud-tempest-qatempest,cloudbase/lis-tempest,cloudbase/lis-tempest,vedujoshi/os_tempest,ntymtsiv/tempest,pandeyop/tempest,itskewpie/tempest,pandeyop/tempest,jaspreetw/tempest,manasi24/jiocloud-tempest-qatempest,queria/my-tempest,vedujoshi/tempest,rakeshmi/tempest,roopali8/tempest,zsoltdudas/lis-tempest,akash1808/tempest,pczerkas/tempest,ebagdasa/tempest,nunogt/tempest,roopali8/tempest,rzarzynski/tempest,tonyli71/tempest,FujitsuEnablingSoftwareTechnologyGmbH/tempest,hpcloud-mon/tempest,hayderimran7/tempest,CiscoSystems/tempest,vmahuli/tempest,JioCloud/tempest,Mirantis/tempest,Juniper/tempest,alinbalutoiu/tempest,varunarya10/tempest,sebrandon1/tempest,jamielennox/tempest,cisco-openstack/tempest,afaheem88/tempest,Juniper/tempest,alinbalutoiu/tempest,Lilywei123/tempest,itskewpie/tempest,armando-migliaccio/tempest,Juraci/tempest,ebagdasa/tempest,yamt/tempest,danielmellado/tempest,hayderimran7/tempest,danielmellado/tempest,varunarya10/tempest,openstack/tempest,Juraci/tempest,redhat-cip/tempest,tudorvio/tempest,xbezdick/tempest,citrix-openstack/build-tempest,Tesora/tesora-tempest,dkalashnik/tempest,FujitsuEnablingSoftwareTechnologyGmbH/tempest,vedujoshi/os_tempest,afaheem88/tempest,pczerkas/tempest,tudorvio/tempest,citrix-openstack/build-tempest,zsoltdudas/lis-tempest,openstack/tempest,afaheem88/tempest_neutron,rzarzynski/tempest,Mirantis/tempest,Vaidyanath/tempest,CiscoSystems/tempest,redhat-cip/tempest,masayukig/tempest,vmahuli/tempest,akash1808/tempest,xbezdick/tempest,dkalashnik/tempest,bigswitch/tempest,NexusIS/tempest,sebrandon1/tempest,Lilywei123/tempest,JioCloud/tempest,hpcloud-mon/tempest,nunogt/tempest,masayukig/tempest,neerja28/Tempest,cisco-openstack/tempest,LIS/lis-tempest,manasi24/tempest,adkerr/tempest,jamielennox/tempest,yamt/tempest,manasi24/tempest,NexusIS/tempest,rakeshmi/tempest,tonyli71/tempest,jaspreetw/tempest,ntymtsiv/tempest,vedujoshi/tempest,eggmaster/tempest