Only throw undefined instruction exception at execution, not at translation stage

Ryujinx/Cpu/State/AInstExceptEventArgs.cs

@@ -0,0 +1,14 @@
+using System;
+
+namespace ChocolArm64.State
+{
+    public class AInstExceptEventArgs : EventArgs
+    {
+        public int Id { get; private set; }
+
+        public AInstExceptEventArgs(int Id)
+        {
+            this.Id = Id;
+        }
+    }
+}