Set compute-feature-enabled.attach_encrypted_volume Tempest option
Set compute-feature-enabled.attach_encrypted_volume Tempest option

This allows setting the new option in Tempest for toggling whether
or not the Cinder encrypted volume tests should run.

Depends-On: I48eba7c645cc1c979fd766ae9c05efb00957f787

Related-Bug: #1463525

Change-Id: I9e12f8dc9e3e6b68dc031351cb081ee2bc6e6cbb

Mahito/devstack,dirkmueller/devstack,wenhuizhang/devstack,noironetworks/devstack,bswartz/devstack,openstack-dev/devstack,flavio-fernandes/devstack,nawawi/openstack,openstack-dev/devstack,prithivm/branch01,flavio-fernandes/devstack,CloudServer/devstack,avvocatodemarchis/devstack,LoHChina/devstack,mssumanth/devstack,HPCHub/devstack,liuquansheng47/devstack,vishnugonela/devstack,samgoon/devstack,mmasaki/devstack,j4/devstack,olivierlemasle/devstack,thomasem/devstack,pczerkas/devstack,pacinete/devstack,pacinete/devstack,herrsechs/devstack,nawawi/openstack,atulpatil301/devstack,thomasem/devstack,CloudServer/devstack,prithivm/branch01,bq-xiao/devstack,dtroyer/devstack,vsham20/devstack,varunarya10/devstack,TwinkleChawla/devstack,wenhuizhang/devstack,group-policy/devstack,dirkmueller/devstack,liuquansheng47/devstack,mssumanth/devstack,ozamiatin/devstack,LoHChina/devstack,herrsechs/devstack,parul24/devstack,costingalan/devstack,avvocatodemarchis/devstack,atulpatil301/devstack,NaokiMiyata/devstack,mc2014/devstack,samgoon/devstack,vsham20/devstack,eharney/devstack,bswartz/devstack,upadhyay-prashant/devstack,j4/devstack,bq-xiao/devstack,group-policy/devstack,richliu/devstack,dtroyer/devstack,ozamiatin/devstack,TwinkleChawla/devstack,Mahito/devstack,pczerkas/devstack,mc2014/devstack,NaokiMiyata/devstack,richliu/devstack,HPCHub/devstack,vishnugonela/devstack,noironetworks/devstack,eharney/devstack,varunarya10/devstack,upadhyay-prashant/devstack,bigswitch/devstack,pombredanne/devstack,olivierlemasle/devstack,bigswitch/devstack,parul24/devstack,mmasaki/devstack,pombredanne/devstack,costingalan/devstack