PCI: tegra: Remove tegra_pcie_scan_bus()

After b97ea289cf ("PCI: Assign resources before drivers claim devices
(pci_scan_root_bus())"), pci_scan_root_bus() no longer adds the devices, so
it is equivalent to tegra_pcie_scan_bus().

Remove tegra_pcie_scan_bus() (the hw.scan method), so we use the generic
pci_scan_root_bus() path.

[bhelgaas: changelog]
Tested-by: Thierry Reding <treding@nvidia.com>
Signed-off-by: Yijing Wang <wangyijing@huawei.com>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Acked-by: Thierry Reding <treding@nvidia.com>

drivers/pci/host/pci-tegra.c

@@ -630,21 +630,6 @@ static int tegra_pcie_map_irq(const struct pci_dev *pdev, u8 slot, u8 pin)
 	return irq;
 }
 
-static struct pci_bus *tegra_pcie_scan_bus(int nr, struct pci_sys_data *sys)
-{
-	struct tegra_pcie *pcie = sys_to_pcie(sys);
-	struct pci_bus *bus;
-
-	bus = pci_create_root_bus(pcie->dev, sys->busnr, &tegra_pcie_ops, sys,
-				  &sys->resources);
-	if (!bus)
-		return NULL;
-
-	pci_scan_child_bus(bus);
-
-	return bus;
-}
-
 static irqreturn_t tegra_pcie_isr(int irq, void *arg)
 {
 	const char *err_msg[] = {
@@ -1831,7 +1816,6 @@ static int tegra_pcie_enable(struct tegra_pcie *pcie)
 	hw.private_data = (void **)&pcie;
 	hw.setup = tegra_pcie_setup;
 	hw.map_irq = tegra_pcie_map_irq;
-	hw.scan = tegra_pcie_scan_bus;
 	hw.ops = &tegra_pcie_ops;
 
 	pci_common_init_dev(pcie->dev, &hw);