[clang] [clang][ExprConst] Allow non-literal types in C++23 (PR #100062)

[via cfe-commits]

https://github.com/Sirraide approved this pull request.

LGTM

Considering that the literal type requirement was quite literally just straight-up removed in C++23, returning early here is basically just doing what the standard did, so this change makes sense to me.

Also, one option would be to move this check up even further to be the first thing we check for in this function (don’t know how expensive the `isLiteralType` check is off the top of my head). I’m not sure it really matters though, so either way seems fine to me.

https://github.com/llvm/llvm-project/pull/100062