soc/intel: Replace config_of_path() with config_of_soc()

The previously provided device path made no difference, all
integrated PCI devices point back to the same chip_info
structure.

Change reduces the exposure of various SA_DEVFN_xx and
PCH_DEVFN_xx from (ugly) soc/pci_devs.h.

Change-Id: Ibf13645fdd3ef7fd3d5c8217bb24d7ede045c790
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/35656
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Aaron Durbin <adurbin@chromium.org>

src/soc/intel/cannonlake/pmc.c

@@ -102,7 +102,7 @@ static void config_deep_sx(uint32_t deepsx_config)
 
 static void pmc_init(void *unused)
 {
-	const config_t *config = config_of_path(SA_DEVFN_ROOT);
+	const config_t *config = config_of_soc();
 
 	rtc_init();