When playing with Mellanox ConnectX-3 virtual function (Device ID = 0x1004),
I found the driver could't be loaded due to
kernel: mlx4_core0: Missing DCS, aborting.(driver_data: 0x0, pci_resource_flags(pdev, 0):0x0)
This is because MLX4_PCI_DEV_IS_VF is assigned to the "class_mask" member
of the struct pci_device_id. Let's fix this by explicit assignment.
And, we don't use ".driver_data = 0" for some lines, because by default the
member is initialized with 0.