[clang-tools-extra] [clang-tidy] Added bugprone-unsequenced-global-accesses check (PR #130421)

[Áron Hárnási via cfe-commits]

ConcreteCactus wrote:

> To keep everything organized, I'd suggest creating a new branch for CSA checker and close this PR (you can always reopen it later).
> 
> For the CSA part, you can start by reading [this developer guide](https://clang-analyzer.llvm.org/checker_dev_manual.html) (probably a bit outdated?). This [original white paper](https://lcs.ios.ac.cn/~xzx/memmodel.pdf) is very helpful in understanding the core principles of the CSA and how it all started. [haoNoQ's guide](https://github.com/haoNoQ/clang-analyzer-guide) gives excellent practical description of how to write checkers and what functions the CSA has.

Thank you, I'll open a new PR when I'm ready with the CSA checker.

https://github.com/llvm/llvm-project/pull/130421