Move DECLARE_GLOBAL_DATA_PTR to file scope

It can be optimised out by the compiler otherwise resulting
in obscure errors like a board not booting.

This has been documented in README since 2006 when these were
first fixed up for GCC 4.x.

Signed-off-by: John Rigby <john.rigby@linaro.org>

Fix some additional places.

Signed-off-by: Wolfgang Denk <wd@denx.de>
Acked-By: Albert ARIBAUD <albert.aribaud@free.fr>
diff --git a/board/renesas/r7780mp/r7780mp.c b/board/renesas/r7780mp/r7780mp.c
index 396e4b6..0b80099 100644
--- a/board/renesas/r7780mp/r7780mp.c
+++ b/board/renesas/r7780mp/r7780mp.c
@@ -26,6 +26,8 @@
 #include <netdev.h>
 #include "r7780mp.h"
 
+DECLARE_GLOBAL_DATA_PTR;
+
 int checkboard(void)
 {
 #if defined(CONFIG_R7780MP)
@@ -46,8 +48,6 @@
 
 int dram_init(void)
 {
-	DECLARE_GLOBAL_DATA_PTR;
-
 	gd->bd->bi_memstart = CONFIG_SYS_SDRAM_BASE;
 	gd->bd->bi_memsize = CONFIG_SYS_SDRAM_SIZE;
 	printf("DRAM:  %dMB\n", CONFIG_SYS_SDRAM_SIZE / (1024 * 1024));