Allow asan for glibc tests.

SANITIZE_HOST will break if we don't allow ASAN.

Change-Id: I0beed82b058db391f633e0ea1098f140497c65d4
diff --git a/tests/Android.mk b/tests/Android.mk
index 14a5e83..2a34ea9 100644
--- a/tests/Android.mk
+++ b/tests/Android.mk
@@ -316,6 +316,8 @@
 bionic-unit-tests-glibc_cppflags := $(test_cppflags)
 bionic-unit-tests-glibc_ldflags := -Wl,--export-dynamic
 
+bionic-unit-tests-glibc_allow_asan := true
+
 module := bionic-unit-tests-glibc
 module_tag := optional
 build_type := host