[compiler-rt] [rtsan][test] Prevent test check from being optimized out in LTO builds (PR #122524)

[Chris Apple via llvm-commits]

https://github.com/cjappl commented:

This code LGTM - I would wait until you hear confirmation from @davidtrevelyan that he agrees with my previous comment.

I'll ping him personally as well to ensure you're not blocked for long

https://github.com/llvm/llvm-project/pull/122524