PCI/IOV: Fix memory leak in pci_iov_add_virtfn()

PCI/IOV: Fix memory leak in pci_iov_add_virtfn()

In the implementation of pci_iov_add_virtfn() the allocated virtfn is
leaked if pci_setup_device() fails. The error handling is not calling
pci_stop_and_remove_bus_device(). Change the goto label to failed2.

Fixes: 156c55325d30 ("PCI: Check for pci_setup_device() failure in pci_iov_add_virtfn()")
Link: https://lore.kernel.org/r/20191125195255.23740-1-navid.emamdoost@gmail.com
Signed-off-by: Navid Emamdoost <navid.emamdoost@gmail.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>