PCI: dwc-plat: Simplify dw_plat_pcie_probe() return values

Save the return value in "ret" for all three cases (DW_PCIE_RC_TYPE,
DW_PCIE_EP_TYPE, default) handled by dw_plat_pcie_probe() and return from a
single place.

[bhelgaas: commit log]
Link: https://lore.kernel.org/r/20220624143428.8334-17-Sergey.Semin@baikalelectronics.ruTested-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Signed-off-by: Serge Semin <Sergey.Semin@baikalelectronics.ru>
Signed-off-by: Bjorn Helgaas <bhelgaas@google.com>
Reviewed-by: Manivannan Sadhasivam <manivannan.sadhasivam@linaro.org>
Reviewed-by: Rob Herring <robh@kernel.org>

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

@@ -143,20 +143,21 @@ static int dw_plat_pcie_probe(struct platform_device *pdev)
 			return -ENODEV;
 
 		ret = dw_plat_add_pcie_port(dw_plat_pcie, pdev);
-		if (ret < 0)
-			return ret;
 		break;
 	case DW_PCIE_EP_TYPE:
 		if (!IS_ENABLED(CONFIG_PCIE_DW_PLAT_EP))
 			return -ENODEV;
 
 		pci->ep.ops = &pcie_ep_ops;
-		return dw_pcie_ep_init(&pci->ep);
+		ret = dw_pcie_ep_init(&pci->ep);
+		break;
 	default:
 		dev_err(dev, "INVALID device type %d\n", dw_plat_pcie->mode);
+		ret = -EINVAL;
+		break;
 	}
 
-	return 0;
+	return ret;
 }
 
 static const struct dw_plat_pcie_of_data dw_plat_pcie_rc_of_data = {