nb/intel/i945/raminit.c: Replace `DIMM0`

Use the actual value as it is more informative.

Change-Id: Id3bd8ccdf79d1e3fdf97cda049f81271bb017ef7
Signed-off-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/52073
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Michael Niewöhner <foss@mniewoehner.de>

src/northbridge/intel/i945/raminit.c

@@ -45,7 +45,7 @@ static int get_dimm_spd_address(struct sys_info *sysinfo, int device)
 	if (sysinfo->spd_addresses)
 		return sysinfo->spd_addresses[device];
 	else
-		return DIMM0 + device;
+		return 0x50 + device;
 
 }