[tlbuild] Support for musl

[Norbert Preining]

Hi all,

> x86_64-alpine-linux-musl

That is not really a triplet but quadruplet, right? Why does Alpine
Linux inject their name here? Quite strange I think.

> > I don't have any specific reason, but on the other hand, I don't want to
> > go to three part names unless there is a clear need. (This is the reason
> > I asked Mojca to use the two-part x86_64-darwinlegacy when that started up.)

In case we ever switch, TLUtils::platform_name as well as some other
function would need to be carefully checked!
So I am also in favor of keeping $CPU-$OSPLUS layout.

Best

Norbert

--
PREINING Norbert                               http://www.preining.info
Accelia Inc.     +    JAIST     +    TeX Live     +    Debian Developer
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