PCI: Move setting pci_host_bridge.busnr out of host drivers

Most host drivers only parse the DT bus range to set the root bus number
in pci_host_bridge.busnr. The ones that don't set busnr are buggy in
that they ignore what's in DT. Let's set busnr in pci_scan_root_bus_bridge()
where we already check for the bus resource and remove setting it in
host drivers.

Link: https://lore.kernel.org/r/20200722022514.1283916-12-robh@kernel.org
Signed-off-by: Rob Herring <robh@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Acked-by: Bjorn Helgaas <bhelgaas@google.com>
Cc: Jingoo Han <jingoohan1@gmail.com>
Cc: Gustavo Pimentel <gustavo.pimentel@synopsys.com>
Cc: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Cc: Bjorn Helgaas <bhelgaas@google.com>
Cc: Thomas Petazzoni <thomas.petazzoni@bootlin.com>
Cc: Will Deacon <will@kernel.org>
Cc: Thierry Reding <thierry.reding@gmail.com>
Cc: Jonathan Hunter <jonathanh@nvidia.com>
Cc: Linus Walleij <linus.walleij@linaro.org>
Cc: Ryder Lee <ryder.lee@mediatek.com>
Cc: Marek Vasut <marek.vasut+renesas@gmail.com>
Cc: Yoshihiro Shimoda <yoshihiro.shimoda.uh@renesas.com>
Cc: linux-tegra@vger.kernel.org
Cc: linux-mediatek@lists.infradead.org
Cc: linux-renesas-soc@vger.kernel.org

drivers/pci/controller/dwc/pcie-designware-host.c

@@ -474,7 +474,6 @@ int dw_pcie_host_init(struct pcie_port *pp)
 	}
 
 	bridge->sysdata = pp;
-	bridge->busnr = pp->busn->start;
 	bridge->ops = &dw_pcie_ops;
 	bridge->map_irq = of_irq_parse_and_map_pci;
 	bridge->swizzle_irq = pci_common_swizzle;