Function mvebu_pcie_hw_rd_conf() does not handle invalid size. So correctly
set read value to all-ones and return appropriate error return value
PCIBIOS_BAD_REGISTER_NUMBER like in mvebu_pcie_hw_wr_conf() function.
Link: https://lore.kernel.org/r/20211125124605.25915-5-pali@kernel.org
Signed-off-by: Pali Rohár <pali@kernel.org>
Signed-off-by: Lorenzo Pieralisi <lorenzo.pieralisi@arm.com>
 
        case 4:
                *val = readl_relaxed(conf_data);
                break;
+       default:
+               *val = 0xffffffff;
+               return PCIBIOS_BAD_REGISTER_NUMBER;
        }
 
        return PCIBIOS_SUCCESSFUL;