of: kill struct of_device

Now that the device tree node pointer has been moved out of struct
of_device and into the common struct device, there isn't anything
unique about of_device anymore.  In fact, there isn't much need
for a separate of_bus when all busses have access to OF style
probing.

arch/powerpc and arch/microblaze are moving away from using the of_bus
and using the regular platform bus instead for mmio devices.  This
patch makes of_device the same as platform_device as a stepping stone
in migrating of_platform_drivers over to the platform bus.

Signed-off-by: Grant Likely <grant.likely@secretlab.ca>
Acked-by: David S. Miller <davem@davemloft.net>
Cc: Michal Simek <monstr@monstr.eu>
Cc: Benjamin Herrenschmidt <benh@kernel.crashing.org>
Cc: Stephen Rothwell <sfr@canb.auug.org.au>

diff --git a/include/linux/of_device.h b/include/linux/of_device.h
index 11651fa..a3ae590 100644
--- a/include/linux/of_device.h
+++ b/include/linux/of_device.h
@@ -3,9 +3,26 @@
 
 #ifdef CONFIG_OF_DEVICE
 #include <linux/device.h>
+#include <linux/platform_device.h>
 #include <linux/of.h>
 #include <linux/mod_devicetable.h>
 
+
+/*
+ * The of_device *was* a kind of "base class" that was a superset of
+ * struct device for use by devices attached to an OF node and probed
+ * using OF properties.  However, the important bit of OF-style
+ * probing, namely the device node pointer, has been moved into the
+ * common struct device when CONFIG_OF is set to make OF-style probing
+ * available to all bus types.  So now, just make of_device and
+ * platform_device equivalent so that current of_platform bus users
+ * can be transparently migrated over to using the platform bus.
+ *
+ * This line will go away once all references to of_device are removed
+ * from the kernel.
+ */
+#define of_device platform_device
+
 #include <asm/of_device.h>
 
 #define	to_of_device(d) container_of(d, struct of_device, dev)