mpc83xx: implement board_add_ram_info

add board_add_ram_info, to make memory diagnostic output more
consistent. u-boot banner output now looks like:

DRAM:  256 MB (DDR1, 64-bit, ECC on)

and for boards with SDRAM on the local bus, a line such as this is
added:

SDRAM: 64 MB (local bus)

also replaced some magic numbers with their equivalent define names.

Signed-off-by: Kim Phillips <kim.phillips@freescale.com>
diff --git a/board/tqm834x/tqm834x.c b/board/tqm834x/tqm834x.c
index 9c35e22..7d0b055 100644
--- a/board/tqm834x/tqm834x.c
+++ b/board/tqm834x/tqm834x.c
@@ -114,7 +114,7 @@
 	/* enable DDR controller */
 	im->ddr.sdram_cfg = (SDRAM_CFG_MEM_EN |
 		SDRAM_CFG_SREN |
-		SDRAM_CFG_SDRAM_TYPE_DDR);
+		SDRAM_CFG_SDRAM_TYPE_DDR1);
 	SYNC;
 
 	/* size detection */
@@ -388,7 +388,7 @@
 	/* don't enable DDR controller yet */
 	im->ddr.sdram_cfg =
 		SDRAM_CFG_SREN |
-		SDRAM_CFG_SDRAM_TYPE_DDR;
+		SDRAM_CFG_SDRAM_TYPE_DDR1;
 	SYNC;
 
 	/* Set SDRAM mode */