Rename services with the official interface names

Ryujinx.Core/OsHle/Services/Ns/IAddOnContentManager.cs

@@ -0,0 +1,37 @@
+using Ryujinx.Core.OsHle.Ipc;
+using System.Collections.Generic;
+
+namespace Ryujinx.Core.OsHle.Services.Ns
+{
+    class IAddOnContentManager : IpcService
+    {
+        private Dictionary<int, ServiceProcessRequest> m_Commands;
+
+        public override IReadOnlyDictionary<int, ServiceProcessRequest> Commands => m_Commands;
+
+        public IAddOnContentManager()
+        {
+            m_Commands = new Dictionary<int, ServiceProcessRequest>()
+            {
+                { 2, CountAddOnContent },
+                { 3, ListAddOnContent  }
+            };
+        }
+
+        public static long CountAddOnContent(ServiceCtx Context)
+        {
+            Context.ResponseData.Write(0);
+
+            return 0;
+        }
+
+        public static long ListAddOnContent(ServiceCtx Context)
+        {
+            //TODO: This is supposed to write a u32 array aswell.
+            //It's unknown what it contains.
+            Context.ResponseData.Write(0);
+
+            return 0;
+        }
+    }
+}