[d3d9] Add device import interop API

[AlpyneDreams]

As requested by @doitsujin in #4497, I have added an API to import existing Vulkan devices. Here is an example of how it could be used to add an async compute queue when creating the device. First, all device creation info is queried with GetDeviceCreateInfo, then the device is created in userspace and passed to ImportDevice. I have tested this and can confirm that it works. Feedback or nits are welcomed!

[WinterSnowfall]

@AlpyneDreams Not sure if you saw it, but there's a warning that's probably worth fixing:

../../../src/d3d9/d3d9_interop.cpp: In member function ‘virtual HRESULT dxvk::D3D9VkInteropInterface::GetDeviceCreateInfo(UINT, D3D9VkDeviceCreateInfo**)’:
Warning: ../../../src/d3d9/d3d9_interop.cpp:92:23: warning: comparison of integer expressions of different signedness: ‘int’ and ‘const size_t’ {aka ‘const unsigned int’} [-Wsign-compare]
   92 |     for (int i = 0; i < queueCount; i++) {
      |                     ~~^~~~~~~~~~~~

[AlpyneDreams]

@WinterSnowfall Thanks, fixed!

[AlpyneDreams]

Rebased.