Allow cxgbe(4) running within a VM to attach to its devices that have been exported via PCI passthrough.
Allow cxgbe(4) running within a VM to attach to its devices that have been
exported via PCI passthrough.

- Do not check for a specific physical function (PF) before claiming a device.
  Different PFs have different device-ids so this check is redundant anyway.

- Obtain the PF# from the WHOAMI register instead of pci_get_function().

- Setup the memory windows using the real BAR0 address, not what the VM says it
  is.

Obtained from:	Chelsio Communications

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