Use after free in OCL wait_for_interrupt API

[mmichal10]

When calling async operation OCL uses _cache_mngt_async_callee_set_result() and _cache_mngt_async_caller_set_result() to communicate whether the caller or the callee is responsible for cleanup.

The API has an invalid assumption - it's not prepared for the callee() part being called before the caller(). This may lead to use-after-free in the caller() code - in case if an async operation is interrupted and the completion function gets called first it marks the completion in struct _cache_mngt_async_context and it frees the context structure instantly. Then, when the caller thread is waked up, it calls _cache_mngt_async_caller_set_result() with the pointer to context, which just has been freed in the completion.

The possible solution is adding reference counter to struct _cache_mngt_async_context