[llvm][utils] Disable lldb formatters for PointerIntPair and PointerUnion

These synthetic providers use expression evaluation and fail in some cases.

Examples:

```
llvm::PointerIntPair<llvm::PointerUnion<const Type *, const ExtQuals *>,
                     Qualifiers::FastWidth> Value;
```

and

```
typedef llvm::PointerUnion<const ValueDecl *, const Expr *, TypeInfoLValue,
                           DynamicAllocLValue>
        PtrTy;
```

Original contribution: D117779

rdar://110791233
rdar://112195543

Differential Revision: https://reviews.llvm.org/D155219