device: Use pcidev_on_root()

Change-Id: Icf34b39d80f6e46d32a39b68f38fb2752c0bcebc
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Signed-off-by: Elyes HAOUAS <ehaouas@noos.fr>
Reviewed-on: https://review.coreboot.org/c/26484
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Piotr Król <piotr.krol@3mdeb.com>
Reviewed-by: Arthur Heymans <arthur@aheymans.xyz>

src/southbridge/intel/common/spi.c

@@ -306,7 +306,7 @@ void spi_init(void)
 #ifdef __SIMPLE_DEVICE__
 	pci_devfn_t dev = PCI_DEV(0, 31, 0);
 #else
-	struct device *dev = dev_find_slot(0, PCI_DEVFN(31, 0));
+	struct device *dev = pcidev_on_root(31, 0);
 #endif
 
 	pci_read_config_dword(dev, 0xf0, &rcba);