Add hwtypes.h to -Landroidbp

Test: update-makefiles produces correct output and building those files.
Change-Id: Ibacc510adca325d71ae11c319f620d961f0a18d1
diff --git a/main.cpp b/main.cpp
index bdecb4c..95cebc3 100644
--- a/main.cpp
+++ b/main.cpp
@@ -761,6 +761,8 @@
                     out << "\"" << pathPrefix << fqName.getInterfaceStubName() << ".h\",\n";
                     out << "\"" << pathPrefix << fqName.getInterfaceProxyName() << ".h\",\n";
                     out << "\"" << pathPrefix << fqName.getInterfacePassthroughName() << ".h\",\n";
+                } else {
+                    out << "\"" << pathPrefix << "hwtypes.h\",\n";
                 }
             });