Since [1], our object files may now contain a GDB script section. These
symbols wind up with multiple instances in the archive but are weak, so
we can safely ignore them in our duplicates check.
This resolves the current CI failures.
[1]: https://github.com/rust-lang/rust/pull/143679
Currently `SymInfo` stores a `Section`, which is just an index:
SymInfo {
section: Section(
SectionIndex(
539,
),
),
...
},
Look up and store the section name instead if possible, with a fallback
to the `Section` debug printing. This makes output more clear and will
allow us to filter by section name.
Rather than re-opening the archive file for each check, add a wrapper
that keeps the data in memory. Additionally, collect the `--target`
argument so it can be used within this crate.
