nb/intel/i440bx: Drop northbridge.h

It declares a function that was either never or no longer implemented.

Change-Id: I714d39374519bff1afb94870d0e84f57db619a1f
Signed-off-by: Keith Hui <buurin@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/40958
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>

src/northbridge/intel/i440bx/northbridge.c

@@ -8,7 +8,6 @@
 #include <device/pci.h>
 #include <device/pci_ids.h>
 #include <cpu/cpu.h>
-#include "northbridge.h"
 #include "i440bx.h"
 
 static void northbridge_init(struct device *dev)

src/northbridge/intel/i440bx/northbridge.h

@@ -1,21 +0,0 @@
-/*
- * This file is part of the coreboot project.
- *
- *
- * 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
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
- *
- * This program is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
- * GNU General Public License for more details.
- */
-
-#ifndef NORTHBRIDGE_INTEL_440BX_H
-#define NORTHBRIDGE_INTEL_440BX_H
-
-extern unsigned int i440bx_scan_root_bus(struct device *root, unsigned int max);
-
-#endif				/* NORTHBRIDGE_INTEL_440BX_H */