board_f: Rename initdram() to dram_init()

This allows us to use the same DRAM init function on all archs. Add a
dummy function for arc, which does not use DRAM init here.

Signed-off-by: Simon Glass <sjg@chromium.org>
[trini: Dummy function on nios2]
Signed-off-by: Tom Rini <trini@konsulko.com>
diff --git a/board/freescale/mpc832xemds/mpc832xemds.c b/board/freescale/mpc832xemds/mpc832xemds.c
index 907ad09..b49e03e 100644
--- a/board/freescale/mpc832xemds/mpc832xemds.c
+++ b/board/freescale/mpc832xemds/mpc832xemds.c
@@ -90,7 +90,7 @@
 
 int fixed_sdram(void);
 
-int initdram(void)
+int dram_init(void)
 {
 	volatile immap_t *im = (immap_t *) CONFIG_SYS_IMMR;
 	u32 msize = 0;