Fix potential makefile bug.

Since multilib is not set every time, it needs to be per module or
there is a change that another target will use the multilib value set
previously.

Change-Id: I5c30e18d5111705cb3f6e3d4cd9ef8a28c9b746c
diff --git a/tests/Android.build.mk b/tests/Android.build.mk
index 5a53685..c1a0f16 100644
--- a/tests/Android.build.mk
+++ b/tests/Android.build.mk
@@ -18,8 +18,8 @@
 
 LOCAL_MODULE := $(module)
 LOCAL_MODULE_TAGS := $(module_tag)
-LOCAL_MULTILIB := $(multilib)
-ifeq ($(multilib),both)
+LOCAL_MULTILIB := $($(module)_multilib)
+ifeq ($(LOCAL_MULTILIB),both)
     LOCAL_MODULE_STEM_32 := $(module)32
     LOCAL_MODULE_STEM_64 := $(module)64
 endif
diff --git a/tests/Android.mk b/tests/Android.mk
index 0014af6..d85e8eb 100644
--- a/tests/Android.mk
+++ b/tests/Android.mk
@@ -221,7 +221,7 @@
 
 module := bionic-unit-tests
 module_tag := optional
-multilib := both
+bionic-unit-tests_multilib := both
 build_type := target
 build_target := NATIVE_TEST
 include $(LOCAL_PATH)/Android.build.mk
@@ -243,7 +243,7 @@
 
 module := bionic-unit-tests-static
 module_tag := optional
-multilib := both
+bionic-unit-tests-static_multilib := both
 build_type := target
 build_target := NATIVE_TEST
 include $(LOCAL_PATH)/Android.build.mk