Build target bzip2 against the NDK.

Change-Id: Ibe76f8eac4dc0db0cc9a6aa214fc005d7561e6a7
diff --git a/Android.mk b/Android.mk
index 35dfec7..2ce58ca 100644
--- a/Android.mk
+++ b/Android.mk
@@ -31,6 +31,10 @@
 LOCAL_SRC_FILES := $(bzlib_files)
 LOCAL_MODULE := libbz
 LOCAL_CFLAGS += -O3 -DUSE_MMAP
+ifneq ($(TARGET_ARCH),x86)
+  LOCAL_NDK_VERSION := 5
+  LOCAL_SDK_VERSION := 9
+endif
 include $(BUILD_STATIC_LIBRARY)
 
 include $(CLEAR_VARS)