soc/intel: Guard TRAP method in ASL

Needed to support build with ACPI_SOC_NVS=n as SMIF object inside
GNVS disappears then.

Change-Id: Ib798187c24996b74d6345080f7d48c3f657eb512
Signed-off-by: Kyösti Mälkki <kyosti.malkki@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/50358
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>

src/southbridge/intel/common/acpi/platform.asl

@@ -17,6 +17,7 @@ Field (POST, ByteAcc, Lock, Preserve)
 	DBG0, 8
 }
 
+#if CONFIG(ACPI_SOC_NVS)
 /* SMI I/O Trap */
 Method(TRAP, 1, Serialized)
 {
@@ -24,6 +25,7 @@ Method(TRAP, 1, Serialized)
 	TRP0 = 0		// Generate trap
 	Return (SMIF)		// Return value of SMI handler
 }
+#endif /* ACPI_SOC_NVS */
 
 /* The _PIC method is called by the OS to choose between interrupt
  * routing via the i8259 interrupt controller or the APIC.