[llvm] [Utils] update_llc_test_checks.py: updated the regexp for ARM target (PR #148287)

[Simon Pilgrim via llvm-commits]

RKSimon wrote:

> But more too, I think. I was wondering what broke `update_llc_test_checks`... Please fix the AArch64 regexes or revert this change.

@MacDue Sorry I missed this :/ 

https://github.com/llvm/llvm-project/pull/148287