[clang] [llvm] [SpecialCaseList] Use glob by default (PR #74809)

[Eli Friedman via cfe-commits]

efriedma-quic wrote:

A report from the field: we had an ignorelist that contained `[cfi-vcall|cfi-nvcall|cfi-icall]`.  This was recommended syntax from the documentation (https://releases.llvm.org/17.0.1/tools/clang/docs/SanitizerSpecialCaseList.html)... but it broke with the transition.  This took a significant effort to track down.

I see the following issues with the transition:

- There was no release note, or any sort of announcement of this breaking change.
- No version of clang produces a diagnostic if you use the affected syntax; the behavior just silently changes.
- The proposed transition period is extremely short; it's impossible to write an ignorelist that works on both clang 17 and clang 19 if you use any regex/glob features other than "*".

https://github.com/llvm/llvm-project/pull/74809