Cleanup cinder-rootwrap support
Cleanup cinder-rootwrap support

cinder_rootwrap support in devstack handled a number of now-abandoned
use cases:

- no $CINDER_DIR/etc/cinder/rootwrap.d (old-style rootwrap)
- using oslo-rootwrap instead of cinder-rootwrap (abandoned experiment)

This change removes unused code paths and aligns
configure_cinder_rootwrap() with configure_nova_rootwrap().

Change-Id: I387808dae0e064cc9c894c74ab78e86124f08dd2

HPCHub/devstack,openstack-dev/devstack,vishnugonela/devstack,rushiagr/devstack,TwinkleChawla/devstack,jamielennox/devstack,pombredanne/devstack,promptworks/devstack,eharney/devstack,nuxeh/devstack,liuquansheng47/devstack,bljgaurav/openstack-test,tianweizhang/devstack,Mahito/devstack,HPCHub/devstack,samgoon/devstack,ozamiatin/devstack,affo/devstack,j4/devstack,affo/devstack,pombredanne/devstack,thomasem/devstack,parul24/devstack,pacinete/devstack,varunarya10/devstack,mmasaki/devstack,BSJAIN92/OpenStack,Mahito/devstack,costingalan/devstack,olivierlemasle/devstack,flavio-fernandes/devstack,BSJAIN92/OpenStack,nawawi/openstack,samgoon/devstack,atulpatil301/devstack,mssumanth/devstack,dirkmueller/devstack,innodee/openstackk,bljgaurav/openstack-test,CloudServer/devstack,bigswitch/devstack,nawawi/openstack,sc68cal/devstack,bswartz/devstack,ozamiatin/devstack,thomasem/devstack,group-policy/devstack,j4/devstack,parul24/devstack,eharney/devstack,NaokiMiyata/devstack,dtroyer/devstack,bswartz/devstack,richliu/devstack,wenhuizhang/devstack,costingalan/devstack,richliu/devstack,noironetworks/devstack,andrewrothstein/devstack,openstack-dev/devstack,CloudServer/devstack,vishnugonela/devstack,bq-xiao/devstack,bq-xiao/devstack,varunarya10/devstack,eshnil2000/devstack,avvocatodemarchis/devstack,prithivm/branch01,JioCloud/devstack,sc68cal/devstack,promptworks/devstack,mc2014/devstack,mmasaki/devstack,upadhyay-prashant/devstack,NaokiMiyata/devstack,rushiagr/devstack,tianweizhang/devstack,pczerkas/devstack,group-policy/devstack,noironetworks/devstack,virtualopensystems/devstack,flavio-fernandes/devstack,andrewrothstein/devstack,sequenceiq/devstack,bigswitch/devstack,Juniper/devstack,prithivm/branch01,dtroyer/devstack,neerja28/Devstack_GlusterFS,vsham20/devstack,srics/devstack,LoHChina/devstack,mssumanth/devstack,mc2014/devstack,herrsechs/devstack,vsham20/devstack,kplus/devstack-moonshot,kplus/devstack-moonshot,herrsechs/devstack,wenhuizhang/devstack,williamthegrey/devstack,nuxeh/devstack,pczerkas/devstack,dirkmueller/devstack,neerja28/Devstack_GlusterFS,olivierlemasle/devstack,pacinete/devstack,TwinkleChawla/devstack,atulpatil301/devstack,avvocatodemarchis/devstack,upadhyay-prashant/devstack,sequenceiq/devstack,liuquansheng47/devstack,LoHChina/devstack