ACPI: Drop device flag wake_capable

The wake_capable ACPI device flag is not necessary, because it is
only used in scan.c for recording the information that _PRW is
present for the given device.  That information is only used by
acpi_add_single_object() to decide whether or not to call
acpi_bus_get_wakeup_device_flags(), so the flag may be dropped
if the _PRW check is moved to acpi_bus_get_wakeup_device_flags().
Moreover, acpi_bus_get_wakeup_device_flags() always returns 0,
so it really should be void.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Signed-off-by: Len Brown <len.brown@intel.com>
diff --git a/include/acpi/acpi_bus.h b/include/acpi/acpi_bus.h
index 20b05cd..78ca429 100644
--- a/include/acpi/acpi_bus.h
+++ b/include/acpi/acpi_bus.h
@@ -148,8 +148,7 @@
 	u32 suprise_removal_ok:1;
 	u32 power_manageable:1;
 	u32 performance_manageable:1;
-	u32 wake_capable:1;	/* Wakeup(_PRW) supported? */
-	u32 reserved:23;
+	u32 reserved:24;
 };
 
 /* File System */