drgn 0.0.30 and libkdumpfile 0.5.5 incompatibility in Arch

Hi Christian,

I think you may already be aware of this, but I wanted to let you know
that there's an incompatibility with drgn 0.0.30-2 and libkdumpfile
0.5.5-1 on Arch. libkdumpfile 0.5.5 changed some APIs in a
backward-incompatible way. Building drgn against the new version fails,
and running a version built against 0.5.4 of course fails due to the
soname change. The current drgn 0.0.30-2 on Arch's repositories was
built against 0.5.4.

Thus a user installing drgn & libkdumpfile on Arch, who is fully
up-to-date, gets this:

ImportError: libkdumpfile.so.10: cannot open shared object file: No such file or directory

The incompatibility is fixed in drgn's main branch by the changes in
[1]. Unfortunately, that was merged after drgn 0.0.30 was released.
Some major changes have been merged since then, so I don't think a
0.0.31 release is likely for a few months. So I think it may be a good
idea to carry the two commits in [1] as downstream patches in a new
0.0.30-3 release. I'd be happy to implement those changes if it'd help.

I'm Ccing the linux-debuggers mailing list for posterity, as well as
Omar and Petr as an FYI.

Thanks,
Stephen

[1]: https://github.com/osandov/drgn/pull/452