PCI: layerscape: Fix arg_count to syscon_regmap_lookup_by_phandle_args()

The arg_count parameter to syscon_regmap_lookup_by_phandle_args()
represents the number of argument cells following the phandle. In this
case, the number of arguments should be 1 instead of 2 since the dt
property looks like this:

  fsl,pcie-scfg = <&scfg 0>;

Without this fix, layerscape-pcie fails with the following message on
LS1043A:

  OF: /soc/pcie@3500000: phandle scfg@1570000 needs 2, found 1
  layerscape-pcie 3500000.pcie: No syscfg phandle specified
  layerscape-pcie 3500000.pcie: probe with driver layerscape-pcie failed with error -22

Link: https://lore.kernel.org/r/[email protected]
Fixes: 149fc35 ("PCI: layerscape: Use syscon_regmap_lookup_by_phandle_args")
Signed-off-by: Ioana Ciornei <[email protected]>
Signed-off-by: Bjorn Helgaas <[email protected]>
Reviewed-by: Frank Li <[email protected]>
Reviewed-by: Krzysztof Kozlowski <[email protected]>
Acked-by: Roy Zang <[email protected]>
Cc: [email protected]

Author: IoanaCiornei

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

@@ -356,7 +356,7 @@ static int ls_pcie_probe(struct platform_device *pdev)
 	if (pcie->drvdata->scfg_support) {
 		pcie->scfg =
 			syscon_regmap_lookup_by_phandle_args(dev->of_node,
-							     "fsl,pcie-scfg", 2,
+							     "fsl,pcie-scfg", 1,
 							     index);
 		if (IS_ERR(pcie->scfg)) {
 			dev_err(dev, "No syscfg phandle specified\n");