[libc++] Remove ABI lists for previous releases
We don't actually update the ABI lists at every release -- it's too much
work, since we'd technically have to do it even for minor releases.
Furthermore, I don't think anybody uses those (I certainly don't rely
on them for anything).
Instead, it is better to rely on the ABI list changelog and the canonical
ABI list that we always keep up to date. If one wants to know what symbols
were shipped in a specific release, that can be discovered easily using
Git, which is a superior tool than keeping textual copies of old versions.
GitOrigin-RevId: 433d0a30c6e64514f9020f34cdebe630c46dbcfb
16 files changed
