dlfcn.dt_runpath* tests are amended to handle LIB

LIB is now expanded to either lib or lib64. Add a new lib
libtest_dt_runpath_y which is under lib or lib64 directory to the tests.

Test: run bionic-unit-tests

Change-Id: Ib051d8cae4d50b452759d594c87126b45bc9e959
diff --git a/tests/Android.bp b/tests/Android.bp
index f8b06c3..cff58e7 100644
--- a/tests/Android.bp
+++ b/tests/Android.bp
@@ -526,6 +526,7 @@
         "libtest_dt_runpath_b",
         "libtest_dt_runpath_c",
         "libtest_dt_runpath_x",
+        "libtest_dt_runpath_y",
         "libatest_simple_zip",
         "libcfi-test",
         "libcfi-test-bad",