Kiewtai stops parsing some Elf files early

There's a bug in the Elf `.ksy` that causes an exception on some well-formed Elf files, I filed it upstream at kaitai-io/kaitai_struct#754

I think they're saying this commit might fix it:

kaitai-io/kaitai_struct_formats#279

Remember to import this fix and rebuild for the next release.

> Note: the exception is harmless, it just stops parsing earlier than expected