interface suggest: thsvsGetAccessInfo

[YunHsiao]

I find the ThsvsAccessType is absolutely a great way to encapsulate synchronizations, but on top of the current design, sometimes we would need a little more fine-grained control, e.g. translate a set of access types to essentially, thsvsVkAccessInfo.

For instance, the current interface becomes inadequate when we try to incorporate subpass dependencies into the system. Say each render pass attachment is given two sets of access types (begin/end), and we'd want to map these to both initial/final layouts and external subpass dependencies.

With something like thsvsGetAccessInfo we can get all the flexibility we'd need for any other synchronization primitives that are not yet fully covered here in the library.