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/stoneyridge/northbridge.c b/src/soc/amd/stoneyridge/northbridge.c
index b95c4cd..a92c3b5 100644
--- a/src/soc/amd/stoneyridge/northbridge.c
+++ b/src/soc/amd/stoneyridge/northbridge.c
@@ -52,9 +52,9 @@
 
 static void create_vga_resource(struct device *dev)
 {
-	if (!dev->link_list)
+	if (!dev->downstream)
 		return;
-	if (!(dev->link_list->bridge_ctrl & PCI_BRIDGE_CTL_VGA))
+	if (!(dev->downstream->bridge_ctrl & PCI_BRIDGE_CTL_VGA))
 		return;
 
 	printk(BIOS_DEBUG, "VGA: %s has VGA device\n",	dev_path(dev));
@@ -67,8 +67,8 @@
 	/* do we need this? */
 	create_vga_resource(dev);
 
-	if (dev->link_list && dev->link_list->children)
-		assign_resources(dev->link_list);
+	if (dev->downstream && dev->downstream->children)
+		assign_resources(dev->downstream);
 }
 
 static void northbridge_init(struct device *dev)