[clang] [clang-format] Fix FormatToken::isSimpleTypeSpecifier() (PR #91712)

[Owen Pan via cfe-commits]

owenca wrote:

> I think this will stop people introducing extra arguments to function
> 
> ...isCpp,isThis,isThat)

I meant to fix the FIXME after I had langded a8279a8bc541, but my previous attempts didn't quite work. Now it seems this solution will stick.

https://github.com/llvm/llvm-project/pull/91712