Don't allow unsupported Vulkan formats to fall back to B8G8R8A8.
Probably better to fail completely than do an illegal copy.
Also remove bad conversion for VK_FORMAT_A2R10G10B10_UNORM_PACK32.
Red and blue channels were reversed, and there's no DXGI equivalent.
Addresses #2796. We can do more later if justified.
Make sure HWND tracking is cleaned up when Vulkan surfaces are
destroyed. Also use unbounded linked list to fix games that leak
surfaces on Alt+Tab like Doom.
Also replace CRITICAL_SECTION with SRWLOCK, both for claimed speed
benefit, and to remove initialization code.