mb/lenovo/t420s: Convert to ASL 2.0 syntax

Change-Id: I6e928c23165abad623ee3c2a26e090b029d55572
Signed-off-by: Elyes HAOUAS <ehaouas@noos.fr>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/46195
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Michael Niewöhner <foss@mniewoehner.de>
diff --git a/src/mainboard/lenovo/t420s/acpi/platform.asl b/src/mainboard/lenovo/t420s/acpi/platform.asl
index 40b9a53..c4becaf 100644
--- a/src/mainboard/lenovo/t420s/acpi/platform.asl
+++ b/src/mainboard/lenovo/t420s/acpi/platform.asl
@@ -16,8 +16,8 @@
 Method(_WAK,1)
 {
 	/* ME may not be up yet. */
-	Store (0, \_TZ.MEB1)
-	Store (0, \_TZ.MEB2)
+	\_TZ.MEB1 = 0
+	\_TZ.MEB2 = 0
 
 	/* Wake the HKEY to init BT/WWAN */
 	\_SB.PCI0.LPCB.EC.HKEY.WAKE (Arg0)