Initial tessellation shader support (#2534)

* Initial tessellation shader support

* Nits

* Re-arrange built-in table

* This is not needed anymore

* PR feedback

Ryujinx.Graphics.Shader/IntermediateRepresentation/OperandHelper.cs

@@ -15,6 +15,11 @@ namespace Ryujinx.Graphics.Shader.IntermediateRepresentation
             return new Operand(OperandType.Attribute, value);
         }
 
+        public static Operand AttributePerPatch(int value)
+        {
+            return new Operand(OperandType.AttributePerPatch, value);
+        }
+
         public static Operand Cbuf(int slot, int offset)
         {
             return new Operand(slot, offset);