Hot attach of disk to a scsi controller will work only if the
controller type is lsilogic-sas or paravirtual.This patch filters
the existing controller for these types, if it doesn't find one it
creates a new scsi controller.
- replaces probeVolume with scsiHostRescan to scan hot attached disks
- fixes substring match of UUID returned from AttachDisk
- changes DetachDisk to take volumePath argument instead of diskID
- fixes delayed failure at mount rather than attach disk
- removes cloning of virtual disk in AttachDisk