Merge pull request #20536 from hedgepigdaniel:fix/ocl-context-create-ownership

Merge pull request #20536 from hedgepigdaniel:fix/ocl-context-create-ownership

docs(core/ocl): clarify ownership of arguments passed into OpenCL related functions

* docs(core/ocl): clarify ownership in OpenCLExecutionContext::create

Although it is technically true that OpenCLExecutionContext::create
calls `clRetainContext` on its context argument, it is misleading
because it does not increase the reference count overall. Clarify that
the ownership of one reference of the passed context and device is
taken.

* docs(core/ocl): document ownership transfer in ocl::Device::fromHandle