[ARM] smp: SCU is used on non-realview platforms

The SCU can be used by non-realview platforms, so make it visible
for other people to use rather than having them copy the header file.

Signed-off-by: Russell King <rmk+kernel@arm.linux.org.uk>

arch/arm/mach-realview/platsmp.c

@@ -23,7 +23,7 @@
 
 #include <mach/board-eb.h>
 #include <mach/board-pb11mp.h>
-#include <mach/scu.h>
+#include <asm/smp_scu.h>
 
 #include "core.h"