don't bind null vertex buffers

src/Ryujinx.Graphics.Metal/EncoderStateManager.cs

@@ -564,6 +564,8 @@ namespace Ryujinx.Graphics.Metal
 
 
             for (int i = 0; i < bufferDescriptors.Length; i++)
+            {
+                if (bufferDescriptors[i].Buffer.Handle.ToIntPtr() != IntPtr.Zero)
                 {
                     buffers.Add(new BufferInfo
                     {
@@ -572,6 +574,7 @@ namespace Ryujinx.Graphics.Metal
                         Index = i
                     });
                 }
+            }
 
             SetBuffers(renderCommandEncoder, buffers);
         }