of/pci: Fix pci_address_to_pio() conversion of CPU address to I/O port

commit 5dbb4c61 upstream.

41f8bba7 ("of/pci: Add pci_register_io_range() and
pci_pio_to_address()") added support for systems with several I/O ranges
described by OF bindings.  It modified pci_address_to_pio() look up the
io_range for a given CPU physical address, but the conversion was wrong.

Fix the conversion of address to I/O port.

[bhelgaas: changelog]
Fixes: 41f8bba7

 ("of/pci: Add pci_register_io_range() and pci_pio_to_address()")
Signed-off-by: Zhichang Yuan <yuanzhichang@hisilicon.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Liviu Dudau <Liviu.Dudau@arm.com>
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>