soc/intel: Use config_of_path(SA_DEVFN_ROOT)

We do not want to disguise somewhat complex function
calls as simple macros.

Change-Id: I53324603c9ece1334c6e09d51338084166f7a585
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/34299
Reviewed-by: Furquan Shaikh <furquan@google.com>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-by: David Guckian
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/soc/intel/cannonlake/smmrelocate.c

@@ -256,7 +256,7 @@ static void setup_ied_area(struct smm_relocation_params *params)
 void smm_info(uintptr_t *perm_smbase, size_t *perm_smsize,
 				size_t *smm_save_state_size)
 {
-	struct device *dev = SA_DEV_ROOT;
+	struct device *dev = pcidev_path_on_root(SA_DEVFN_ROOT);
 
 	printk(BIOS_DEBUG, "Setting up SMI for CPU\n");