nb/intel/x4x: Use new fixed BAR accessors

Some cases break reproducibility if refactored, and are left as-is.

Tested with BUILD_TIMELESS=1, Asus P5QL PRO remains identical.

Change-Id: I163995c0b107860449c2f36ad63e4e4ca52decb2
Signed-off-by: Angel Pons <th3fanbus@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/51878
Reviewed-by: Nico Huber <nico.h@gmx.de>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
diff --git a/src/northbridge/intel/x4x/romstage.c b/src/northbridge/intel/x4x/romstage.c
index c70c1fb..1695ddd 100644
--- a/src/northbridge/intel/x4x/romstage.c
+++ b/src/northbridge/intel/x4x/romstage.c
@@ -37,7 +37,7 @@
 
 	if (s3_resume)
 		boot_path = BOOT_PATH_RESUME;
-	if (MCHBAR32(PMSTS_MCHBAR) & PMSTS_WARM_RESET)
+	if (mchbar_read32(PMSTS_MCHBAR) & PMSTS_WARM_RESET)
 		boot_path = BOOT_PATH_WARM_RESET;
 
 	mb_get_spd_map(spd_addr_map);