device: Replace ugly cases of dev_find_slot()

These few cases lacked a proper devfn parameter in the
form of PCI_DEVFN(dev, fn).

Change-Id: Iad0b214df12dee65360d07e887a960b0c73a3e4f
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Signed-off-by: Elyes HAOUAS <ehaouas@noos.fr>
Reviewed-on: https://review.coreboot.org/c/26481
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Werner Zeh <werner.zeh@siemens.com>
diff --git a/src/northbridge/intel/x4x/northbridge.c b/src/northbridge/intel/x4x/northbridge.c
index af3019c..ab58c94 100644
--- a/src/northbridge/intel/x4x/northbridge.c
+++ b/src/northbridge/intel/x4x/northbridge.c
@@ -239,7 +239,7 @@
 {
 	int dev, fn, bit_base;
 
-	struct device *const d0f0 = dev_find_slot(0, 0);
+	struct device *const d0f0 = pcidev_on_root(0x0, 0);
 
 	/* Hide internal functions based on devicetree info. */
 	for (dev = 6; dev > 0; --dev) {