PCI: Pass bridge device, not bus, when updating bridge windows

pci_setup_bridge_io(), pci_setup_bridge_mmio(), and
pci_setup_bridge_mmio_pref() program the windows of PCI-PCI bridges.
Previously they accepted a pointer to the pci_bus of the secondary bus,
then looked up the bridge leading to that bus.  Pass the bridge directly,
which will make it more convenient for future callers.

No functional change.

[bhelgaas: changelog, split into separate patch]
Link: https://bugzilla.kernel.org/show_bug.cgi?id=85491


Reported-by: Marek Kordik <kordikmarek@gmail.com>
Fixes: 5b285415 ("PCI: Restrict 64-bit prefetchable bridge windows to 64-bit resources")
Signed-off-by: Yinghai Lu <yinghai@kernel.org>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
CC: stable@vger.kernel.org	# v3.16+