[PATCH] ppc64: Squash warning in ppc64 xics.c

From: David Gibson <david@gibson.dropbear.id.au>

xics.c uses ppc64_boot_msg() without prototype, this fixes it by inclding
<asm/machdep.h>.

arch/ppc64/kernel/xics.c

@@ -25,6 +25,7 @@
 #include <asm/xics.h>
 #include <asm/ppcdebug.h>
 #include <asm/hvcall.h>
+#include <asm/machdep.h>
 
 #include "i8259.h"