util/autoport: Move SPDX header before defines in dsdt.asl

Macros were being printed before the SPDX header in dsdt.asl, so fix
this. Previous output:

#define BRIGHTNESS_UP \_SB.PCI0.GFX0.INCB
#define BRIGHTNESS_DOWN \_SB.PCI0.GFX0.DECB
/* SPDX-License-Identifier: GPL-2.0-only */

Change-Id: Idebdcf816911af9d262a114c86461e6fa5bfd1f8
Signed-off-by: Nicholas Chin <nic.c3.14@gmail.com>
Reviewed-on: https://review.coreboot.org/c/coreboot/+/83187
Reviewed-by: Felix Singer <service+coreboot-gerrit@felixsinger.de>
Tested-by: build bot (Jenkins) <no-reply@coreboot.org>
Reviewed-by: Angel Pons <th3fanbus@gmail.com>

util/autoport/main.go

@@ -827,6 +827,7 @@ func main() {
 
 	dsdt := Create(ctx, "dsdt.asl")
 	defer dsdt.Close()
+	Add_gpl(dsdt)
 
 	for _, define := range DSDTDefines {
 		if define.Comment != "" {
@@ -835,7 +836,6 @@ func main() {
 		dsdt.WriteString("#define " + define.Key + " " + define.Value + "\n")
 	}
 
-	Add_gpl(dsdt)
 	dsdt.WriteString(
 `#include <acpi/acpi.h>