PM / Runtime: Implement the pm_generic_runtime functions for CONFIG_PM

The pm_generic_runtime_suspend|resume functions were implemented within
CONFIG_PM_RUNTIME.

As we also may use runtime PM callbacks during system suspend, to put
devices into low power state, we need to move the implementation of
pm_generic_runtime_suspend|resume to CONFIG_PM.

This change gives a power domain provision to invoke a platform
driver's runtime PM callback from a power domain's system PM callback.
This were earlier prevented by the platform bus, since it uses the
pm_generic_runtime_suspend|resume functions as runtime PM callbacks.

Cc: Kevin Hilman <khilman@linaro.org>
Cc: Alan Stern <stern@rowland.harvard.edu>
Signed-off-by: Ulf Hansson <ulf.hansson@linaro.org>
Signed-off-by: Rafael J. Wysocki <rafael.j.wysocki@intel.com>
diff --git a/drivers/base/power/generic_ops.c b/drivers/base/power/generic_ops.c
index 5ee030a..a2e55bf 100644
--- a/drivers/base/power/generic_ops.c
+++ b/drivers/base/power/generic_ops.c
@@ -10,7 +10,7 @@
 #include <linux/pm_runtime.h>
 #include <linux/export.h>
 
-#ifdef CONFIG_PM_RUNTIME
+#ifdef CONFIG_PM
 /**
  * pm_generic_runtime_suspend - Generic runtime suspend callback for subsystems.
  * @dev: Device to suspend.
@@ -48,7 +48,7 @@
 	return ret;
 }
 EXPORT_SYMBOL_GPL(pm_generic_runtime_resume);
-#endif /* CONFIG_PM_RUNTIME */
+#endif /* CONFIG_PM */
 
 #ifdef CONFIG_PM_SLEEP
 /**