pci_get_bus_and_slot() is restrictive such that it assumes domain=0 as
where a PCI device is present. This restricts the device drivers to be
reused for other domain numbers.

Getting ready to remove pci_get_bus_and_slot() function in favor of
pci_get_domain_bus_and_slot().

When we have a pci_dev, extract the domain number from it.

The config access syscalls don't allow the user to supply a domain number,
so they only work on devices in domain 0, so we can just hard-code that.
Signed-off-by: Sinan Kaya <okaya@codeaurora.org>
[bhelgaas: squash quirk & syscall patches together]
Signed-off-by: Bjorn Helgaas <helgaas@kernel.org>