PCI: histb: Drop error data fabrication when config read fails

If config pci_ops.read() methods return failure, the PCI_OP_READ() and
PCI_USER_READ_CONFIG() wrappers use PCI_SET_ERROR_RESPONSE() to set the
data value, so there's no need to set it in the pci_ops.read() methods
themselves.

Drop the unnecessary data value fabrication when pci_ops.read() fails.

Link: https://lore.kernel.org/r/7da7ea[e-mail]
Signed-off-by: Naveen Naidu <[e-mail]>
Signed-off-by: Bjorn Helgaas <[e-mail]>

drivers/pci/controller/dwc/pcie-histb.c

···
 {
 	struct dw_pcie *pci = to_dw_pcie_from_pp(bus->sysdata);
 
-	if (PCI_SLOT(devfn)) {
-		*val = ~0;
+	if (PCI_SLOT(devfn))
 		return PCIBIOS_DEVICE_NOT_FOUND;
-	}
 
 	*val = dw_pcie_read_dbi(pci, where, size);
 	return PCIBIOS_SUCCESSFUL;