PCI: dwc: Skip PCIE_MSI_INTR0* programming if MSI is disabled

If MSI is disabled, there's no need to program PCIE_MSI_INTR0_MASK
and PCIE_MSI_INTR0_ENABLE registers.

Link: https://lore.kernel.org/r/20201009155436.27e67238@xhacker.debianSigned-off-by: NJisheng Zhang <Jisheng.Zhang@synaptics.com>
Signed-off-by: NLorenzo Pieralisi <lorenzo.pieralisi@arm.com>
Reviewed-by: NRob Herring <robh@kernel.org>
Acked-by: NGustavo Pimentel <gustavo.pimentel@synopsys.com>

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

@@ -528,7 +528,7 @@ void dw_pcie_setup_rc(struct pcie_port *pp)
 
 	dw_pcie_setup(pci);
 
-	if (!pp->ops->msi_host_init) {
+	if (pci_msi_enabled() && !pp->ops->msi_host_init) {
 		num_ctrls = pp->num_vectors / MAX_MSI_IRQS_PER_CTRL;
 
 		/* Initialize IRQ Status array */