[clang] [clang][bytecode] Use in Expr::tryEvaluateObjectSize() (PR #179197)

[Timm Baeder via cfe-commits]

tbaederr wrote:

That should hit the `if (!Ptr.isBlockPointer())` at the beginning of `evaluateBuiltinObjectSize()` though. I removed the special case for function pointers anyway, let's see.

https://github.com/llvm/llvm-project/pull/179197