Move solution and projects to src

src/Ryujinx.Graphics.Video/IVp9Decoder.cs

@@ -0,0 +1,14 @@
+using System;
+
+namespace Ryujinx.Graphics.Video
+{
+    public interface IVp9Decoder : IDecoder
+    {
+        bool Decode(
+            ref Vp9PictureInfo pictureInfo,
+            ISurface output,
+            ReadOnlySpan<byte> bitstream,
+            ReadOnlySpan<Vp9MvRef> mvsIn,
+            Span<Vp9MvRef> mvsOut);
+    }
+}