PM: Add flag for devices capable of generating run-time wake-up events

Apparently, there are devices that can wake up the system from sleep
states and yet are incapable of generating wake-up events at run
time.  Thus, introduce a flag indicating if given device is capable
of generating run-time wake-up events.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

Documentation/power/runtime_pm.txt

@@ -71,9 +71,9 @@ what to do to handle the device).
     purpose).
 
 In particular, if the driver requires remote wakeup capability for proper
-functioning and device_may_wakeup() returns 'false' for the device, then
+functioning and device_run_wake() returns 'false' for the device, then
 ->runtime_suspend() should return -EBUSY.  On the other hand, if
-device_may_wakeup() returns 'true' for the device and the device is put
+device_run_wake() returns 'true' for the device and the device is put
 into a low power state during the execution of its bus type's
 ->runtime_suspend(), it is expected that remote wake-up (i.e. hardware mechanism
 allowing the device to request a change of its power state, such as PCI PME)
@@ -215,6 +215,9 @@ defined in include/linux/pm.h:
       being executed for that device and it is not practical to wait for the
       suspend to complete; means "start a resume as soon as you've suspended"
 
+  unsigned int run_wake;
+    - set if the device is capable of generating run-time wake-up events
+
   enum rpm_status runtime_status;
     - the run-time PM status of the device; this field's initial value is
       RPM_SUSPENDED, which means that each device is initially regarded by the