PCI: Remove reset argument from pci_iov_{add,remove}_virtfn()

The "reset" argument passed to pci_iov_add_virtfn() and
pci_iov_remove_virtfn() is always zero since 46cb7b1b

 ("PCI: Remove
unused SR-IOV VF Migration support")

Remove the argument together with the associated code.

Signed-off-by: Jan H. Schönherr <jschoenh@amazon.de>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Russell Currey <ruscur@russell.cc>