Fix restoring a backup volume to a larger volume
Fix restoring a backup volume to a larger volume

We cannot restore a backup to a larger volume on ceph because it
fails with status "error_restoring". This patch adds read/write
permissions to volumes pool for backup user. We need such permissions
to change volume size during restoring backup when the backup is
smaller than a volume.

Change-Id: I794c1126bcee4e07baf5a9dcfee779fd61da5636
Closes-Bug: 1519749

nawawi/openstack,richliu/devstack,dirkmueller/devstack,Mahito/devstack,dtroyer/devstack,nawawi/openstack,openstack-dev/devstack,Mahito/devstack,dtroyer/devstack,openstack-dev/devstack,avvocatodemarchis/devstack,dirkmueller/devstack,noironetworks/devstack,group-policy/devstack,bswartz/devstack,noironetworks/devstack,group-policy/devstack,mssumanth/devstack,bswartz/devstack,avvocatodemarchis/devstack,samgoon/devstack,mssumanth/devstack,richliu/devstack,bigswitch/devstack,bigswitch/devstack,samgoon/devstack