device,nb/amd: Deduplicate add_more_links()

This function is duplicated in many AMD northbridge files, and all
the definitions have started to diverge somewhat. This moves a single
copy into device utils and deletes the rest. The function definition
from nb/amd/amdfam10 was chosen to be kept, since it contains several
fixes from commit 59d609217b (AMD fam10: Fix add_more_links) that
the others don't have.

For the ease of diffing, the checkpatch lints and other small cleanups
will be done in a follow-up patch.

Change-Id: I5ea73126092449db3f18e19ac0660439313072de
Signed-off-by: Jacob Garber <jgarber1@ualberta.ca>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/33237
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-by: Paul Menzel <paulepanter@users.sourceforge.net>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
diff --git a/src/device/device_util.c b/src/device/device_util.c
index 47df305..e2370a1 100644
--- a/src/device/device_util.c
+++ b/src/device/device_util.c
@@ -654,6 +654,42 @@
 	return 0;
 }
 
+void add_more_links(struct device *dev, unsigned total_links)
+{
+	struct bus *link, *last = NULL;
+	int link_num = -1;
+
+	for (link = dev->link_list; link; link = link->next) {
+		if (link_num < link->link_num)
+			link_num = link->link_num;
+		last = link;
+	}
+
+	if (last) {
+		int links = total_links - (link_num + 1);
+		if (links > 0) {
+			link = malloc(links*sizeof(*link));
+			if (!link)
+				die("Couldn't allocate more links!\n");
+			memset(link, 0, links*sizeof(*link));
+			last->next = link;
+		}
+	} else {
+		link = malloc(total_links*sizeof(*link));
+		memset(link, 0, total_links*sizeof(*link));
+		dev->link_list = link;
+	}
+
+	for (link_num = link_num + 1; link_num < total_links; link_num++) {
+		link->link_num = link_num;
+		link->dev = dev;
+		link->next = link + 1;
+		last = link;
+		link = link->next;
+	}
+	last->next = NULL;
+}
+
 static void resource_tree(const struct device *root, int debug_level, int depth)
 {
 	int i = 0;