davinci: fix compile warning: <mach/da8xx.h>: #include <linux/platform_device.h>

This hushes the following warning:

arch/arm/mach-davinci/include/mach/da8xx.h:104: warning: ‘struct platform_device’
declared inside parameter list
arch/arm/mach-davinci/include/mach/da8xx.h:104: warning: its scope is only this
definition or declaration, which is probably not what you want
Signed-off-by: Sergei Shtylyov <sshtylyov@ru.mvista.com>
Signed-off-by: Kevin Hilman <khilman@deeprootsystems.com>

arch/arm/mach-davinci/include/mach/da8xx.h

@@ -3,7 +3,7 @@
  *
  * Author: Mark A. Greer <mgreer@mvista.com>
  *
- * 2007, 2009 (c) MontaVista Software, Inc. This file is licensed under
+ * 2007, 2009-2010 (c) MontaVista Software, Inc. This file is licensed under
  * the terms of the GNU General Public License version 2. This program
  * is licensed "as is" without any warranty of any kind, whether express
  * or implied.
@@ -13,7 +13,9 @@
 
 #include <video/da8xx-fb.h>
 
+#include <linux/platform_device.h>
 #include <linux/davinci_emac.h>
+
 #include <mach/serial.h>
 #include <mach/edma.h>
 #include <mach/i2c.h>