ACPI/PCI: handle multiple _OSC

The pci_osc_control_set() function can be called for the ACPI object
that doesn't have _OSC method. In this case, acpi_get_osc_data() would
allocate a useless memory region. To avoid this, we need to check the
existence of _OSC before calling acpi_get_osc_data(). Here is a patch
to fix this problem in pci_osc_control_set.

Signed-off-by: Kenji Kaneshige <[e-mail]>
Signed-off-by: Jesse Barnes <[e-mail]>

drivers/pci/pci-acpi.c

···
 {
 	acpi_status	status;
 	u32		ctrlset;
-	struct acpi_osc_data *osc_data = acpi_get_osc_data(handle);
+	acpi_handle tmp;
+	struct acpi_osc_data *osc_data;
 
+	status = acpi_get_handle(handle, "_OSC", &tmp);
+	if (ACPI_FAILURE(status))
+		return status;
+
+	osc_data = acpi_get_osc_data(handle);
 	if (!osc_data) {
 		printk(KERN_ERR "acpi osc data array is full\n");
 		return AE_ERROR;