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/amd/common/block/lpc/lpc.c b/src/soc/amd/common/block/lpc/lpc.c
index c076361..a90fc3e 100644
--- a/src/soc/amd/common/block/lpc/lpc.c
+++ b/src/soc/amd/common/block/lpc/lpc.c
@@ -280,10 +280,10 @@
 {
 	struct device *child;
 
-	if (!dev->link_list)
+	if (!dev->downstream)
 		return;
 
-	for (child = dev->link_list->children; child; child = child->sibling) {
+	for (child = dev->downstream->children; child; child = child->sibling) {
 		if (!child->enabled)
 			continue;
 		if (child->path.type != DEVICE_PATH_PNP)