Semaphore Payloads for Semaphores Created from D3D12 Fences

Creating a dedicated issue for this task from #696:

We need to clarify exactly when semaphore payloads must be provided, especially for semaphores created from D3D12 fences.

Should semaphores created from D3D12 fences be considered binary semaphores?

Read issue #696 and the surrounding OpenCL-Docs specification text about semaphore payloads and semaphores created from D3D12 fences. Determine when payloads are required and whether those semaphores are binary; done means the rules and classification are resolved and documented.

Written by the indexing model from the issue text.