srcver: use libmakepkg for printing version
srcver: use libmakepkg for printing version

The PKGBUILD is already sourced priorly by makepkg, so precautions to
limit effects from sourcing have no effect. Use libmakepkg to print the
version instead.

As aur-build, use --buildscript which defaults to `PKGBUILD`.

AladW/aurutils,AladW/aurutils