sh: Fix up NUMA build error with se7722_defconfig.

Signed-off-by: Paul Mundt <lethal@linux-sh.org>
diff --git a/arch/sh/include/asm/mmzone.h b/arch/sh/include/asm/mmzone.h
index 2969253..7f5363b 100644
--- a/arch/sh/include/asm/mmzone.h
+++ b/arch/sh/include/asm/mmzone.h
@@ -4,6 +4,8 @@
 #ifdef __KERNEL__
 
 #ifdef CONFIG_NEED_MULTIPLE_NODES
+#include <linux/numa.h>
+
 extern struct pglist_data *node_data[];
 #define NODE_DATA(nid)		(node_data[nid])