GetVMAttachedToVolUsingAdminCli() should allow for same volume name on different datastores

[govint]

When testing with restarting docker with two volumes of the same name on different datastores, GetVMAttachedToVolUsingAdminCli() returned an error that the expected output had more than one match.

Its ok to have multiple volumes of the same name and on different datastores. GetVMAttachedToVolUsingAdminCli() should check the datastore as well, otherwise some tests don't necessarily work ok, with a false alarm.

2017/06/28 20:32:46 Attaching volume [restart_test_volume_666978] on VM[192.168.31.85]
2017/06/28 20:32:49 Confirming attached status for volume [restart_test_volume_666978]
2017/06/28 20:32:52 Admin cli output is expected to consist of two elements only - volume name and attached-to-vm status. Actual output
restart_test_volume_666978 detached <------- this volume is on datastore1
restart_test_volume_666978 Ubuntu.16.10 <------ this volume is on vsandatastore
exit status 1

[govint]

Will be fixed via #1566