[llvm] [llvm-mca][Darwin] Fix crash on .subsections_via_symbols in asm input (PR #182694)

[dan rouhana via llvm-commits]

dr7ana wrote:

@boomanaiden154 Apologies, I didn't have the option on the web UI to merge (was looking [here](https://llvm.org/docs/Contributing.html#how-to-submit-a-patch)), so I clicked the Update button which probably used the noreply email as it was a [web operation](https://docs.github.com/en/account-and-profile/how-tos/email-preferences/setting-your-commit-email-address). 

I confirmed my .gitconfig is already set to use my real e-mail, so the most recent rebase/push should be correct I think...

https://github.com/llvm/llvm-project/pull/182694