device/device.h: Rename busses for clarity

This renames bus to upstream and link_list to downstream.

Signed-off-by: Arthur Heymans <arthur@aheymans.xyz>
Change-Id: I80a81b6b8606e450ff180add9439481ec28c2420
Reviewed-on: https://review.coreboot.org/c/coreboot/+/78330
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Felix Held <felix-coreboot@felixheld.de>
diff --git a/src/northbridge/intel/i440bx/northbridge.c b/src/northbridge/intel/i440bx/northbridge.c
index d588197..0a72cb7 100644
--- a/src/northbridge/intel/i440bx/northbridge.c
+++ b/src/northbridge/intel/i440bx/northbridge.c
@@ -34,8 +34,8 @@
 
 	pci_domain_read_resources(dev);
 
-	pci_tolm = find_pci_tolm(dev->link_list);
-	mc_dev = dev->link_list->children;
+	pci_tolm = find_pci_tolm(dev->downstream);
+	mc_dev = dev->downstream->children;
 	if (mc_dev) {
 		unsigned long tomk, tolmk;
 		int idx;