[Orc] Allow LLJITBuilder's CreateObjectLinkingLayer to return errors

It can be useful for an ObjectLinkingLayerCreator to allow callee errors to get propagated to the builder. Specifically, this is the case when the ObjectLayer uses the EHFrameRegistrationPlugin, because it requires a TPCEHFrameRegistrar and instantiation for it may fail (e.g. if the required registration symbols are missing in the target process).

Reviewed By: lhames

Differential Revision: https://reviews.llvm.org/D94690