[linker] Add Java.Interop.GenericMarshaler to Sdk assemblies

Context: #4141
Context: 130905e

The `Java.Interop.GenericMarshaler` namespace was put in separate
assembly in Java.Interop repo.

Let make linker be aware of it, so that it can be linked in
LinkSdkOnly mode.

Author: radekdoulik

src/Xamarin.Android.Build.Tasks/Linker/MonoDroid.Tuner/MonoDroidProfile.cs

@@ -17,7 +17,9 @@ protected override bool IsProduct (string assemblyName)
 
 		protected override bool IsSdk (string assemblyName)
 		{
-			return assemblyName.Equals ("Java.Interop", StringComparison.Ordinal) || base.IsSdk (assemblyName);
+			return assemblyName.Equals ("Java.Interop", StringComparison.Ordinal)
+			       || assemblyName.Equals ("Java.Interop.GenericMarshaler", StringComparison.Ordinal)
+			       || base.IsSdk (assemblyName);
 		}
 	}
 }