Discussion: extra copying justification

Nobody has claimed this yet.

Hello.

I'm wondering if there's any specific reason of this copyings:
```
newBuf := data[:fv.Length]
fv.buf = make([]byte, fv.Length)
copy(fv.buf, newBuf)
```

I've removed copying in my sandbox and everything still works. Also:
```
BenchmarkFianoUEFIParse-8 26365509 ns/op 730 B/op 10 allocs/op
```
vs
```
BenchmarkFianoUEFIParse-8 33305961 ns/op 33555673 B/op 13 allocs/op
```

So this copyings creates a lot of extra memory consumption for nothing.

~~Also in my case this copyings creates some obstacles, because I'm trying to calculate offsets by subtracting one pointer from another.~~ (this point is not relevant anymore)

```
[xaionaro@void fiano]$ go test ./...
ok github.com/linuxboot/fiano/cmds/fmap 0.097s
ok github.com/linuxboot/fiano/cmds/fspinfo 0.024s
? github.com/linuxboot/fiano/cmds/glzma [no test files]
? github.com/linuxboot/fiano/cmds/guid2english [no test files]
? github.com/linuxboot/fiano/cmds/utk [no test files]
ok github.com/linuxboot/fiano/integration 4.587s
ok github.com/linuxboot/fiano/pkg/compression 6.119s
ok github.com/linuxboot/fiano/pkg/fmap 0.030s
ok github.com/linuxboot/fiano/pkg/fsp 0.012s
ok github.com/linuxboot/fiano/pkg/guid 0.041s
ok github.com/linuxboot/fiano/pkg/guid2english 0.020s
? github.com/linuxboot/fiano/pkg/knownguids [no test files]
ok github.com/linuxboot/fiano/pkg/uefi 0.004s
? github.com/linuxboot/fiano/pkg/unicode [no test files]
? github.com/linuxboot/fiano/pkg/utk [no test files]
ok github.com/linuxboot/fiano/pkg/visitors 6.907s
? github.com/linuxboot/fiano/scripts/checklicenses [no test files]
? github.com/linuxboot/fiano/scripts/namecollect [no test files]
[xaionaro@void fiano]$ go test ./... -race
ok github.com/linuxboot/fiano/cmds/fmap 4.040s
ok github.com/linuxboot/fiano/cmds/fspinfo 1.010s
? github.com/linuxboot/fiano/cmds/glzma [no test files]
? github.com/linuxboot/fiano/cmds/guid2english [no test files]
? github.com/linuxboot/fiano/cmds/utk [no test files]
ok github.com/linuxboot/fiano/integration 20.109s
ok github.com/linuxboot/fiano/pkg/compression 51.295s
ok github.com/linuxboot/fiano/pkg/fmap 1.082s
ok github.com/linuxboot/fiano/pkg/fsp 1.009s
ok github.com/linuxboot/fiano/pkg/guid 1.026s
ok github.com/linuxboot/fiano/pkg/guid2english 1.422s
? github.com/linuxboot/fiano/pkg/knownguids [no test files]
ok github.com/linuxboot/fiano/pkg/uefi 1.030s
? github.com/linuxboot/fiano/pkg/unicode [no test files]
? github.com/linuxboot/fiano/pkg/utk [no test files]
ok github.com/linuxboot/fiano/pkg/visitors 106.731s
? github.com/linuxboot/fiano/scripts/checklicenses [no test files]
? github.com/linuxboot/fiano/scripts/namecollect [no test files]
```

So the question is would you accept a PR where I just remove this copyings?

Start by locating the buffer-copy sequence shown in the issue and review how the buffer is used after parsing. Run the reported benchmarks, then go test ./... and go test ./... -race; done means confirming the copy can be removed without changing ownership, lifetime, parsing behavior, or test results.

Written by the indexing model from the issue text.