{soc,superio}/acpi: Replace Subtract(a,b,c) with ASL 2.0 syntax

Replace `Subtract (a, b, c)` with `c = a - b`.

Change-Id: If6455ab2c91619f884abae227f1ac2e2c2af6ba9
Signed-off-by: Felix Singer <felixsinger@posteo.net>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/70625
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Elyes Haouas <ehaouas@noos.fr>
diff --git a/src/soc/intel/baytrail/acpi/southcluster.asl b/src/soc/intel/baytrail/acpi/southcluster.asl
index 31efcb9..551bf08 100644
--- a/src/soc/intel/baytrail/acpi/southcluster.asl
+++ b/src/soc/intel/baytrail/acpi/southcluster.asl
@@ -159,7 +159,7 @@
 	{
 		Store (LPFW, LMIN)
 		Store (0x00100000, LLEN)
-		Subtract (LMIN + LLEN, One, LMAX)
+		LMAX = LMIN + LLEN - One
 	}
 	Else
 	{