Revert "Relocate volume to compliant datastore"

Commit 4be8913520f5e9fe4109ade101da9509e4a83360 introduced a regression
which causes failures during cinder volume re-attach. This patch reverts
commit 4be8913520f5e9fe4109ade101da9509e4a83360 as an immediate fix.

Closes-Bug: #1379830
Change-Id: I5dfbd45533489c3c81db8d256bbfd2f85614a357
(cherry picked from commit 48cb82971e0418f9a629e2b39d0433dc2c0e6919)