VMware: Use vm_mode constants

Address missing changes for the vm_mode type from
commit 8fcd1b2c73dad8e2a7b4d299da270934fd5328cc.

Change-Id: Id03dc089af064969501ee2fc9d965a2028f901e4
Co-authored-by: Gary Kotton <gkotton@vmware.com>
Retry on closing of luks encrypted volume in case device is busy

We're seeing races in the gate on detach of an encrypted volume where
the device is busy so the detach fails, which causes the delete of the
volume on the cinder side to fail because the volume is still in use and
then Tempest times out waiting for the volume to be deleted.

This simply adds a retry to close the encryption device.  I use
attempts=3 since that's what we use for lvremove.

Closes-Bug: #1374458

Change-Id: Ia0667da7dee247ba8c3338b296244b2a71d1045d
Merge "Retry on closing of luks encrypted volume in case device is busy"
Merge "VMware: Use vm_mode constants"