Add BINDER_IPC_32BIT to CFLAGS unless TARGET_USES_64_BIT_BINDER is true

Change-Id: I96c643123b0314c361b7f48a18d5c22c660d4ff5
diff --git a/libs/binder/Android.mk b/libs/binder/Android.mk
index f3f8daf..3c6b8ad 100644
--- a/libs/binder/Android.mk
+++ b/libs/binder/Android.mk
@@ -42,6 +42,9 @@
 LOCAL_MODULE := libbinder
 LOCAL_SHARED_LIBRARIES := liblog libcutils libutils
 LOCAL_SRC_FILES := $(sources)
+ifneq ($(TARGET_USES_64_BIT_BINDER),true)
+LOCAL_CFLAGS += -DBINDER_IPC_32BIT=1
+endif
 include $(BUILD_SHARED_LIBRARY)
 
 include $(CLEAR_VARS)
@@ -49,4 +52,7 @@
 LOCAL_MODULE := libbinder
 LOCAL_STATIC_LIBRARIES += libutils
 LOCAL_SRC_FILES := $(sources)
+ifneq ($(TARGET_USES_64_BIT_BINDER),true)
+LOCAL_CFLAGS += -DBINDER_IPC_32BIT=1
+endif
 include $(BUILD_STATIC_LIBRARY)