Change storage test generator

1. Now it finds disks from all local storages instead of checking PRIMARY disk only.
; This is useful when XS has set up that primary disk is not local SR disk. (i.e. Boot from SAN)
2. Updated how to find bus/pci info of storage that was not working well with some setup
3. All the buses, that have local disk(s) attached and local SR is created, will be selected to test.
; Generally only 1 local SR would be present. But now it is possible to run multiple local storage interface testing by adding additional local SR.
4. Make storage test to run against given SR
; This is required for 3 above.