[M] Change in coreboot[main]: util/autoport: Extend Add_gpl to more files

[Angel Pons (Code Review)]

Attention is currently required from: Nicholas Chin.

Angel Pons has posted comments on this change by Nicholas Chin. ( https://review.coreboot.org/c/coreboot/+/83184?usp=email )

Change subject: util/autoport: Extend Add_gpl to more files
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Patch Set 3:

(1 comment)

File util/autoport/main.go:

https://review.coreboot.org/c/coreboot/+/83184/comment/30571138_3c0abb1e?usp... :
PS2, Line 882: 		gma.WriteString(`-- SPDX-License-Identifier: GPL-2.0-or-later
> I made a note about it in the commit message. […]

I kind of do, because consistency: pretty much every `gma-mainboard.ads` uses `GPL-2.0-or-later`

How about parametrising the license name? You can use an enum:

```
type License string

const (
    GPL2_only License = "GPL-2.0-only"
    GPL2_or_later     = "GPL-2.0-or-later"
    CC_PDDC           = "CC-PDDC"
    MIT               = "MIT"
    BSD2              = "BSD-2-Clause"
    BSD2_patent       = "BSD-2-Clause-Patent"
    BSD3              = "BSD-3-Clause"
)
```

We may not need all of these, but I added them for the sake of example