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/drivers/net/r8168.c b/src/drivers/net/r8168.c
index 70a0f63..6d93ed2 100644
--- a/src/drivers/net/r8168.c
+++ b/src/drivers/net/r8168.c
@@ -364,7 +364,7 @@
 static void r8168_net_fill_ssdt(const struct device *dev)
 {
 	struct drivers_net_config *config = dev->chip_info;
-	const char *path = acpi_device_path(dev->bus->dev);
+	const char *path = acpi_device_path(dev->upstream->dev);
 	u32 address;
 
 	if (!path || !config)