PM / Runtime: Allow helpers to be called by early platform drivers

Runtime PM helper functions, like pm_runtime_get_sync(), cannot be
called by early platform device drivers, because the devices' power
management locks are not initialized at that time.  This is quite
inconvenient, so modify early_platform_add_devices() to initialize
the devices power management locks as appropriate and make sure that
they won't be initialized more than once if an early platform
device is going to be used as a regular one later.

Signed-off-by: Rafael J. Wysocki <rjw@sisk.pl>
diff --git a/drivers/base/platform.c b/drivers/base/platform.c
index a1a7225..d51514b 100644
--- a/drivers/base/platform.c
+++ b/drivers/base/platform.c
@@ -22,6 +22,7 @@
 #include <linux/pm_runtime.h>
 
 #include "base.h"
+#include "power/power.h"
 
 #define to_platform_driver(drv)	(container_of((drv), struct platform_driver, \
 				 driver))
@@ -948,6 +949,7 @@
 		dev = &devs[i]->dev;
 
 		if (!dev->devres_head.next) {
+			pm_runtime_early_init(dev);
 			INIT_LIST_HEAD(&dev->devres_head);
 			list_add_tail(&dev->devres_head,
 				      &early_platform_device_list);