An earlier commit cd006086 ("ata_piix:
defer disks to the Hyper-V drivers by default") broke MS Virtual PC
guests. Hyper-V guests and Virtual PC guests have nearly identical DMI
info. As a result the driver does currently ignore the emulated hardware
in Virtual PC guests and defers the handling to hv_blkvsc. Since Virtual
PC does not offer paravirtualized drivers no disks will be found in the
guest.

One difference in the DMI info is the product version. This patch adds a
match for MS Virtual PC 2007 and "unignores" the emulated hardware.

This was reported for openSuSE 12.1 in bugzilla:
https://bugzilla.novell.com/show_bug.cgi?id=737532

Here is a detailed list of DMI info from example guests:

hwinfo --bios:

virtual pc guest:

  System Info: #1
    Manufacturer: "Microsoft Corporation"
    Product: "Virtual Machine"
    Version: "VS2005R2"
    Serial: "3178-9905-1533-4840-9282-0569-59"
    UUID: undefined, but settable
    Wake-up: 0x06 (Power Switch)
  Board Info: #2
    Manufacturer: "Microsoft Corporation"
    Product: "Virtual Machine"
    Version: "5.0"
    Serial: "3178-9905-1533-4840-9282-0569-59"
  Chassis Info: #3
    Manufacturer: "Microsoft Corporation"
    Version: "5.0"
    Serial: "3178-9905-1533-4840-9282-0569-59"
    Asset Tag: "7188-3705-6309-9738-9645-0364-00"
    Type: 0x03 (Desktop)
    Bootup State: 0x03 (Safe)
    Power Supply State: 0x03 (Safe)
    Thermal State: 0x01 (Other)
    Security Status: 0x01 (Other)

win2k8 guest:

  System Info: #1
    Manufacturer: "Microsoft Corporation"
    Product: "Virtual Machine"
    Version: "7.0"
    Serial: "9106-3420-9819-5495-1514-2075-48"
    UUID: undefined, but settable
    Wake-up: 0x06 (Power Switch)
  Board Info: #2
    Manufacturer: "Microsoft Corporation"
    Product: "Virtual Machine"
    Version: "7.0"
    Serial: "9106-3420-9819-5495-1514-2075-48"
  Chassis Info: #3
    Manufacturer: "Microsoft Corporation"
    Version: "7.0"
    Serial: "9106-3420-9819-5495-1514-2075-48"
    Asset Tag: "7076-9522-6699-1042-9501-1785-77"
    Type: 0x03 (Desktop)
    Bootup State: 0x03 (Safe)
    Power Supply State: 0x03 (Safe)
    Thermal State: 0x01 (Other)
    Security Status: 0x01 (Other)

win2k12 guest:

  System Info: #1
    Manufacturer: "Microsoft Corporation"
    Product: "Virtual Machine"
    Version: "7.0"
    Serial: "8179-1954-0187-0085-3868-2270-14"
    UUID: undefined, but settable
    Wake-up: 0x06 (Power Switch)
  Board Info: #2
    Manufacturer: "Microsoft Corporation"
    Product: "Virtual Machine"
    Version: "7.0"
    Serial: "8179-1954-0187-0085-3868-2270-14"
  Chassis Info: #3
    Manufacturer: "Microsoft Corporation"
    Version: "7.0"
    Serial: "8179-1954-0187-0085-3868-2270-14"
    Asset Tag: "8374-0485-4557-6331-0620-5845-25"
    Type: 0x03 (Desktop)
    Bootup State: 0x03 (Safe)
    Power Supply State: 0x03 (Safe)
    Thermal State: 0x01 (Other)
    Security Status: 0x01 (Other)
Signed-off-by: Olaf Hering <olaf@aepfle.de>
Signed-off-by: Jeff Garzik <jgarzik@redhat.com>