Update SpriteEffect.cs to honor the Viewport settings

[stromkos]

Added position and min/max depth values from the GraphicsDevice.Viewport.
See #8074

[mrhelmut]

This seems correct, though it'd be best to wait for graphical unit tests to come back online before we merge just to make sure.

[Mindfulplays]

Are we sure this is correct? glViewport (or any platform Viewport call such as Metal/DX) should apply vp.X/Y etc already. And hence, the original code is correct. Note that the backbuffer that the sprite effect renders onto has the correct width/height within the viewport (not the screen). So the shader correctly multiplies normalized coords with the matrix W/H.

(Viewport X/Y is generally 0,0 so it's hard to test this. But, on Android, GraphicsDevice::ResetClientBounds explicitly sets viewport with a x/y offset due to safe-area/cutouts - which is a common enough use case so you can verify this quickly)

I recommend not touching position.