Win32+Angle: reuse the first created D3D11 display

[MrJul]

What does the pull request do?

On Windows, when Angle + DirectX 11 are used (these are the defaults), a call to D3D11CreateDevice is made to ensure that D3D11 works correctly. However, this call is very slow: on my system, it's ≈65ms spent in native code (DirectX lib + Nvidia drivers).

When the renderer starts, it makes the same call again. It's a bit faster, but not by much (≈50ms).
This PR reuses the first created display if possible, improving startup time in all scenarios, NativeAOT included.

Remarks

AngleWin32PlatformGraphics has been split into two classes: D3D9 (shared) and D3D11 (non shared) since they use two distinct paths, making clearer which members are used.

IPlatformGraphicsOpenGlContextFactory isn't implemented anymore for D3D9: its CreateContext implementation was always throwing anyways. The only usage is in OpenGlControlBase, which will fail a line earlier in this case:

Avalonia/src/Avalonia.OpenGL/Controls/OpenGlControlBase.cs

Lines 84 to 85 in 4f08bce

	var contextFactory = AvaloniaLocator.Current.GetRequiredService<IPlatformGraphicsOpenGlContextFactory>();
	ctx = contextFactory.CreateContext(null);

[avaloniaui-team]

You can test this PR using the following package version. 11.0.999-cibuild0038512-beta. (feed url: https://nuget-feed-all.avaloniaui.net/v3/index.json) [PRBUILDID]

[avaloniaui-team]

You can test this PR using the following package version. 11.0.999-cibuild0039133-beta. (feed url: https://nuget-feed-all.avaloniaui.net/v3/index.json) [PRBUILDID]