PM / Runtime: Correct documentation of pm_runtime_irq_safe()

The description of pm_runtime_irq_safe() has to be updated to follow
the code after commit 02b26774 (PM / Runtime: Allow _put_sync() from
interrupts-disabled context).
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
Acked-by: Kevin Hilman <khilman@ti.com>

Documentation/power/runtime_pm.txt

@@ -431,8 +431,7 @@ drivers/base/power/runtime.c and include/linux/pm_runtime.h:
 
   void pm_runtime_irq_safe(struct device *dev);
     - set the power.irq_safe flag for the device, causing the runtime-PM
-      suspend and resume callbacks (but not the idle callback) to be invoked
-      with interrupts disabled
+      callbacks to be invoked with interrupts off
 
   void pm_runtime_mark_last_busy(struct device *dev);
     - set the power.last_busy field to the current time