Fixed datera-cinder vs upstream cinder conflict
Fixed datera-cinder vs upstream cinder conflict

If the patchset under test had Datera driver changes (what we currently
try to achieve with openstack review gating), it had eventually been
overwritten by our Datera github cinder-driver code. I reversed the
order of the driver checkouts so now if a review patchset is provided,
it will be tested properly

Datera/cinder-driver,Datera/cinder-driver