[compiler-rt] [AIX][PGO] Handle atexit functions when dlclose'ing shared libraries (PR #102940)

[Wael Yehia via llvm-commits]

w2yehia wrote:

@rorth thanks for looking into it. I don't have access to a solaris, if you're able to make it pass locally on a solaris system, I can help integrate the fix into the testcase (I imagine there has to be some platform specific options on the RUN command), or you can post a PR that I can test on AIX and ppc Linux for you.

https://github.com/llvm/llvm-project/pull/102940