VulkanSwapChain::acquire returns early on VK_SUBOPTIMAL_KHR instead of treating it as successful acquire

[NDYDHHC]

In VulkanSwapChain::acquire, the current logic does:

call mPlatform->acquire(...)
if result != VK_SUCCESS, return early
This means VK_SUBOPTIMAL_KHR is treated as a failure, even though it is a valid successful acquire result in Vulkan (with a hint that swapchain is suboptimal).