sh: x3 - fix setup_bootmem_node() compile error with shx3_defconfig

This makes sure the function prototype for setup_bootmem_node() gets
included. The file setup-shx3.c does not compile otherwise for
CONFIG_NUMA=n.
Signed-off-by: Magnus Damm <damm@igel.co.jp>
Signed-off-by: Paul Mundt <lethal@linux-sh.org>

arch/sh/kernel/cpu/sh4a/setup-shx3.c

@@ -11,6 +11,7 @@
 #include <linux/init.h>
 #include <linux/serial.h>
 #include <linux/io.h>
+#include <asm/mmzone.h>
 #include <asm/sci.h>
 
 static struct plat_sci_port sci_platform_data[] = {