llvm-readobj is an internal testing tool for binary formats. Its output and
command line options do not need to be stable. It isn't supposed to be part of a
build process.
llvm-readelf was created as a user-facing utility and its interface intends to
be compatible with GNU readelf (unless there are good reasons not to).
The two tools have mostly compatible options. -s and -t are noticeable
exceptions due to history. I think the cost of keeping the inconsistency overweighs the
little history-compatible benefit and hinders transition from cl::opt to
OptTable, so let's change it.
No need to change this test, I think. You still want -s in the list, and you already have -S there. You might also want to add -t, but it's not really importantn, in my opinion.