makeVulkan
Creates a Graphite backend semaphore wrapping a Vulkan VkSemaphore.
The returned BackendSemaphore does not take ownership of semaphorePtr and will not delete the Vulkan semaphore when it is closed.
Return
a backend semaphore wrapping the Vulkan semaphore.
Parameters
semaphorePtr
native pointer (VkSemaphore) to wrap.