tree/acpi: Replace Not(a) with ASL 2.0 syntax

Replace `Not (a)` with `~a`.

Change-Id: I53993fb7b46b3614d18ee001323f17efacbf04c1
Signed-off-by: Felix Singer <felixsinger@posteo.net>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/71513
Reviewed-by: Elyes Haouas <ehaouas@noos.fr>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>

src/ec/quanta/it8518/acpi/ec.asl

@@ -547,7 +547,7 @@ Device (EC0)
 		\PWRS = ACPW
 
 		// Initialize LID switch state
-		\LIDS = NOT(HPLD)
+		\LIDS = ~HPLD
 
 		// Enable OS control of fan speed
 		// TODO FCOS = One