soc/amd/stoneyridge/acpi: Convert to ASL 2.0

Change-Id: I71c296cdc0180a2832aeb51434de3302a54b5db8
Signed-off-by: Elyes HAOUAS <ehaouas@noos.fr>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/50323
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>

src/soc/amd/stoneyridge/acpi/pci_int.asl

@@ -109,7 +109,7 @@
 		{
 			\_SB.CIRQ()
 		}
-		Store(Arg0, PICM)
+		PICM = Arg0
 	}
 
 	Method(CIRQ, 0x00, NotSerialized){

src/soc/amd/stoneyridge/acpi/sb_pci0_fch.asl

@@ -583,7 +583,7 @@ Method(PWGC,2, Serialized)
 		Local1 = ~Arg0
 		Local0 &= Local1
 	}
-	Store(Local0, PGA3)
+	PGA3 = Local0
 	if (Arg0 == 0x20) { /* if SwUsb3SlpShutdown */
 		Local0 = PGA3
 		Local0 &= Arg0