Add a force fail for non-bionic xfail test.

Test: xfail test passes on host.
Change-Id: I6c4ddd3f3dc5541b126d9dd31b1fcff9d34819e6
diff --git a/tests/dl_test.cpp b/tests/dl_test.cpp
index cb98cae..e7cf0d6 100644
--- a/tests/dl_test.cpp
+++ b/tests/dl_test.cpp
@@ -153,6 +153,9 @@
   ExecTestHelper eth;
   eth.SetArgs({ helper.c_str(), nullptr });
   eth.Run([&]() { execve(helper.c_str(), eth.GetArgs(), eth.GetEnv()); }, 0, nullptr);
+#else
+  // Force a failure when not compiled for bionic so the test is considered a pass.
+  ASSERT_TRUE(false);
 #endif
 }