board_f: Drop return value from initdram()

At present we cannot use this function as an init sequence call without a
wrapper, since it returns the RAM size. Adjust it to set the RAM size in
global_data instead, and return 0 on success.

Signed-off-by: Simon Glass <sjg@chromium.org>
Reviewed-by: Stefan Roese <sr@denx.de>
diff --git a/board/cobra5272/cobra5272.c b/board/cobra5272/cobra5272.c
index 9d4554d..4836676 100644
--- a/board/cobra5272/cobra5272.c
+++ b/board/cobra5272/cobra5272.c
@@ -8,6 +8,7 @@
 #include <common.h>
 #include <asm/immap.h>
 
+DECLARE_GLOBAL_DATA_PTR;
 
 int checkboard (void)
 {
@@ -16,7 +17,7 @@
 	return 0;
 };
 
-phys_size_t initdram(void)
+int initdram(void)
 {
 	volatile sdramctrl_t *sdp = (sdramctrl_t *) (MMAP_SDRAM);
 
@@ -26,7 +27,9 @@
 	/* Dummy write to start SDRAM */
 	*((volatile unsigned long *) 0) = 0;
 
-	return CONFIG_SYS_SDRAM_SIZE * 1024 * 1024;
+	gd->ram_size = CONFIG_SYS_SDRAM_SIZE * 1024 * 1024;
+
+	return 0;
 };
 
 int testdram (void)