[llvm] [AArch64][PAC] Support BLRA* instructions in SLS Hardening pass (PR #97605)

[Anatoly Trosinenko via llvm-commits]

https://github.com/atrosinenko commented:

Thank you for your review @kbeyls, I updated a few straightforward places. I need a bit more time to think how to update the comments better.

https://github.com/llvm/llvm-project/pull/97605