PCI: layerscape: Modify the MSIX to the doorbell mode

dw_pcie_ep_raise_msix_irq was never called in the exisitng driver
before, because the ls1046a platform don't support the MSIX feature
and msix_capable was always set to false.
Now that add the ls1088a platform with MSIX support, use the doorbell
method to support the MSIX feature.

Link: https://lore.kernel.org/r/20200918080024.13639-9-Zhiqiang.Hou@nxp.comSigned-off-by: NXiaowei Bao <xiaowei.bao@nxp.com>
Signed-off-by: NHou Zhiqiang <Zhiqiang.Hou@nxp.com>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: NAndrew Murray <andrew.murray@arm.com>

drivers/pci/controller/dwc/pci-layerscape-ep.c

@@ -79,7 +79,8 @@ static int ls_pcie_ep_raise_irq(struct dw_pcie_ep *ep, u8 func_no,
 	case PCI_EPC_IRQ_MSI:
 		return dw_pcie_ep_raise_msi_irq(ep, func_no, interrupt_num);
 	case PCI_EPC_IRQ_MSIX:
-		return dw_pcie_ep_raise_msix_irq(ep, func_no, interrupt_num);
+		return dw_pcie_ep_raise_msix_irq_doorbell(ep, func_no,
+							  interrupt_num);
 	default:
 		dev_err(pci->dev, "UNKNOWN IRQ type\n");
 		return -EINVAL;