PCI ACPI: fix uninitialized variable in __pci_osc_support_set

Fix uninitialized variable in __pci_osc_support_set().

If the ACPI namespace doesn't have any device object corresponding to
the specified hid, 'retval' in __pci_osc_support_set() is not changed
by the acpi_query_osc() callback. Since 'retval' is not initizlized in
the current implementation, the contents of 'retval' is undefined in
this case. This causes a mis-handling of ctrlset_buf[OSC_SUPPORT_TYPE]
and will cause an unexpected result in the subsequent
pci_osc_control_set() call as a result.
Signed-off-by: NKenji Kaneshige <kaneshige.kenji@jp.fujitsu.com>
Signed-off-by: NJesse Barnes <jbarnes@virtuousgeek.org>

drivers/pci/pci-acpi.c

@@ -166,7 +166,7 @@ acpi_run_osc (
 acpi_status __pci_osc_support_set(u32 flags, const char *hid)
 {
 	u32 temp;
-	acpi_status retval;
+	acpi_status retval = AE_NOT_FOUND;
 
 	if (!(flags & OSC_SUPPORT_MASKS)) {
 		return AE_TYPE;