[mtouch] Pass features not available on iOS to linker (#4426)

external/mono

@@ -1 +1 @@
-Subproject commit 639ca72904d12bbe149c93645ff31374524e5c10
+Subproject commit 16538b28e365f5288541ffb112d965f5d191847d

tools/mtouch/Tuning.cs

@@ -134,6 +134,7 @@ namespace MonoTouch.Tuner {
 			context.SetParameter ("debug-build", options.DebugBuild.ToString ());
 			context.StaticRegistrar = options.Target.StaticRegistrar;
 			context.Target = options.Target;
+			context.ExcludedFeatures = new [] { "remoting", "com", "sre" };
 			options.LinkContext = context;
 
 			return context;