[tlbuild] Support for musl

[Norbert Preining]

Hi,

thanks for the deployment explanantion. I have now adapted our
travis.yml in line with yours, the only changes are:
- only build releases for the musl
- add env var tldir=i386-linuxmusl and x86_64-linuxmusl
- for no musl dont build docker
- change the before_deploy to
    if [ -n "$package" ]; then mv inst/bin/x86_64-pc-linux-gnu inst/bin/$tldir ; tar czvf ${package} -C inst/bin .; fi
  to get a the directory, too.

Hope that flies.

Norbert

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