northbridge/intel/i440bx: Move NB macro to i440bx.h

This move makes the NB macro more widely available,
in preparation for implementing get_top_of_ram().

Change-Id: Icd8e82cfdfdccb662b2139d0e5d1d5af72cbae7f
Signed-off-by: Keith Hui <buurin@gmail.com>
Reviewed-on: https://review.coreboot.org/20675
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Reviewed-by: Martin Roth <martinroth@google.com>
diff --git a/src/northbridge/intel/i440bx/raminit.c b/src/northbridge/intel/i440bx/raminit.c
index 86e9595..67d8d3f 100644
--- a/src/northbridge/intel/i440bx/raminit.c
+++ b/src/northbridge/intel/i440bx/raminit.c
@@ -2,7 +2,7 @@
  * This file is part of the coreboot project.
  *
  * Copyright (C) 2007-2008 Uwe Hermann <uwe@hermann-uwe.de>
- * Copyright (C) 2010 Keith Hui <buurin@gmail.com>
+ * Copyright (C) 2010,2017 Keith Hui <buurin@gmail.com>
  *
  * This program is free software; you can redistribute it and/or modify
  * it under the terms of the GNU General Public License as published by
@@ -25,11 +25,9 @@
 #include "i440bx.h"
 #include "raminit.h"
 
-/*-----------------------------------------------------------------------------
-Macros and definitions.
------------------------------------------------------------------------------*/
-
-#define NB PCI_DEV(0, 0, 0)
+/*
+ * Macros and definitions
+ */
 
 /* Debugging macros. */
 #if IS_ENABLED(CONFIG_DEBUG_RAM_SETUP)