ec/lenovo/h8/acpi: Replace LNotEqual(a,b) with ASL 2.0 syntax

Replace `LNotEqual(a, b)` with `a != b`.

Change-Id: Ic114e097a08488106554ce2dec61fa219d7cf1d0
Signed-off-by: Felix Singer <felixsinger@posteo.net>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/60700
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Sean Rhodes <sean@starlabs.systems>

src/ec/lenovo/h8/acpi/thinkpad.asl

@@ -35,13 +35,13 @@ Device (HKEY)
 	Method (MHKP, 0, NotSerialized)
 	{
 		Store (BTN, Local0)
-		If (LNotEqual (Local0, Zero)) {
+		If (Local0 != 0) {
 			Store (Zero, BTN)
 			Local0 += 0x1000
 			Return (Local0)
 		}
 		Store (BTAB, Local0)
-		If (LNotEqual (Local0, Zero)) {
+		If (Local0 != 0) {
 			Store (Zero, BTAB)
 			Local0 += 0x5000
 			Return (Local0)