powerpc/5121: move fsl-diu-fb.h to include/linux

Some DIU structures will be used in platform code in
subsequent MPC5121 DIU patch, so we move this header
to be able to include it elsewhere.
Signed-off-by: NAnatolij Gustschin <agust@denx.de>
Acked-by: NTimur Tabi <timur@freescale.com>
Signed-off-by: NGrant Likely <grant.likely@secretlab.ca>

drivers/video/fsl-diu-fb.c

@@ -34,7 +34,7 @@
 #include <linux/of_platform.h>
 
 #include <sysdev/fsl_soc.h>
-#include "fsl-diu-fb.h"
+#include <linux/fsl-diu-fb.h>
 
 /*
  * These parameters give default parameters