PM / Runtime: Add might_sleep() to runtime PM functions

Some of the entry points to pm runtime are not safe to
call in atomic context unless pm_runtime_irq_safe() has
been called.  Inspecting the code, it is not immediately
obvious that the functions sleep at all, as they run
inside a spin_lock_irqsave, but under some conditions
they can drop the lock and turn on irqs.

If a driver incorrectly calls the pm_runtime apis, it can
cause sleeping and irq processing when it expects to stay
in atomic context.

Add might_sleep_if to the majority of the __pm_runtime_* entry points
to enforce correct usage.

Add pm_runtime_put_sync_autosuspend to the list of
functions that can be called in atomic context.

Signed-off-by: Colin Cross <ccross@android.com>
Reviewed-by: Kevin Hilman <khilman@ti.com>
Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>

Documentation/power/runtime_pm.txt

@@ -484,6 +484,7 @@ pm_runtime_resume()
 pm_runtime_get_sync()
 pm_runtime_put_sync()
 pm_runtime_put_sync_suspend()
+pm_runtime_put_sync_autosuspend()
 
 5. Runtime PM Initialization, Device Probing and Removal