PCI: Update pcie_ports 'auto' behavior for non-ACPI platforms

The pcie_ports parameter, which defaults to 'auto', allows a user
to specify if PCIe port services are disabled ('compat'), always
enabled ('native'), or only used when allowed by the BIOS
('auto').

Where CONFIG_ACPI isn't enabled, as is often the case for non
x86/ia64 platforms, the 'auto' behavior results in that of
'compat'. Thus in order to use port services on these platforms
'pcie_ports=native' must be added to the kernel command line.

This patch results in the 'native' behavior being followed where
'auto' is selected and ACPI is not enabled.
Signed-off-by: NAndrew Murray <amurray@embedded-bits.co.uk>
Signed-off-by: NBjorn Helgaas <bhelgaas@google.com>

drivers/pci/pcie/portdrv_core.c

@@ -260,13 +260,14 @@ static int get_port_device_capability(struct pci_dev *dev)
 	if (pcie_ports_disabled)
 		return 0;
 
-	err = pcie_port_platform_notify(dev, &cap_mask);
-	if (!pcie_ports_auto) {
-		cap_mask = PCIE_PORT_SERVICE_PME | PCIE_PORT_SERVICE_HP
-				| PCIE_PORT_SERVICE_VC;
-		if (pci_aer_available())
-			cap_mask |= PCIE_PORT_SERVICE_AER;
-	} else if (err) {
+	cap_mask = PCIE_PORT_SERVICE_PME | PCIE_PORT_SERVICE_HP
+			| PCIE_PORT_SERVICE_VC;
+	if (pci_aer_available())
+		cap_mask |= PCIE_PORT_SERVICE_AER;
+
+	if (pcie_ports_auto) {
+		err = pcie_port_platform_notify(dev, &cap_mask);
+		if (err)
 			return 0;
 	}