board: constify struct node_info array

Add 'const' (also 'static' in some places) to struct node_info
arrays to save memory footprint.

Signed-off-by: Masahiro Yamada <yamada.masahiro@socionext.com>
diff --git a/board/freescale/bsc9131rdb/bsc9131rdb.c b/board/freescale/bsc9131rdb/bsc9131rdb.c
index 367152f..9d9c83f 100644
--- a/board/freescale/bsc9131rdb/bsc9131rdb.c
+++ b/board/freescale/bsc9131rdb/bsc9131rdb.c
@@ -53,7 +53,7 @@
 
 #if defined(CONFIG_OF_BOARD_SETUP)
 #ifdef CONFIG_FDT_FIXUP_PARTITIONS
-struct node_info nodes[] = {
+static const struct node_info nodes[] = {
 	{ "fsl,ifc-nand",		MTD_DEV_TYPE_NAND, },
 };
 #endif