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/soc/intel/common/block/xhci/xhci.c b/src/soc/intel/common/block/xhci/xhci.c
index ff6fbf0..03ed578 100644
--- a/src/soc/intel/common/block/xhci/xhci.c
+++ b/src/soc/intel/common/block/xhci/xhci.c
@@ -92,8 +92,8 @@
 		return;
 	}
 
-	while ((hub = dev_bus_each_child(xhci->link_list, hub)) != NULL) {
-		while ((port = dev_bus_each_child(hub->link_list, port)) != NULL) {
+	while ((hub = dev_bus_each_child(xhci->downstream, hub)) != NULL) {
+		while ((port = dev_bus_each_child(hub->downstream, port)) != NULL) {
 			enable = true;
 			config = config_of(port);
 			if (config->type == UPC_TYPE_INTERNAL) {