[llvm-readelf] --section-details: display SHF_COMPRESSED headers

readelf --section-details displays ch_type/ch_size/ch_addralign for
a SHF_COMPRESSED section. Port the feature. There is a small difference
that readelf doesn't display `[<corrupt>]` for an empty section while
we do.

Reviewed By: jhenderson

Differential Revision: https://reviews.llvm.org/D136636