soc/intel: Use config_of()

Change-Id: I0727a6b327410197cf32f598d1312737744386b3
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/34328
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Furquan Shaikh <furquan@google.com>
Reviewed-by: David Guckian

src/soc/intel/broadwell/serialio.c

@@ -170,7 +170,7 @@ static void serialio_init_once(int acpi_mode)
 
 static void serialio_init(struct device *dev)
 {
-	config_t *config = dev->chip_info;
+	config_t *config = config_of(dev);
 	struct resource *bar0, *bar1;
 	int sio_index = -1;
 	u32 reg32;