[llvm] [clang] [PowerPC] Support local-dynamic TLS relocation on AIX (PR #66316)

[Amy Kwan via cfe-commits]

https://github.com/amy-kwan commented:

I imagine this will be updated after 4b932d84f48e0f3f42c769a5ca7ce6623ab62f2e so I plan to review again after.

https://github.com/llvm/llvm-project/pull/66316