mfd: Add platform data pointer back

Now that we have a way to pass MFD cells down to the sub drivers,
we can gradually get rid of mfd_data by putting the platform pointer
back in place.

Signed-off-by: Samuel Ortiz <sameo@linux.intel.com>
diff --git a/include/linux/mfd/core.h b/include/linux/mfd/core.h
index aef23309..68c13e5 100644
--- a/include/linux/mfd/core.h
+++ b/include/linux/mfd/core.h
@@ -36,6 +36,10 @@
 	/* mfd_data can be used to pass data to client drivers */
 	void			*mfd_data;
 
+	/* platform data passed to the sub devices drivers */
+	void			*platform_data;
+	size_t			pdata_size;
+
 	/*
 	 * These resources can be specified relative to the parent device.
 	 * For accessing hardware you should use resources from the platform dev