GNU make doesn't need libc++.

Test: readelf -aW | grep NEEDED
Change-Id: I4f0fbdd014a8976ecfb887c5b7df850a26e591ed
diff --git a/Android.bp b/Android.bp
index f779e8b..8a67870 100644
--- a/Android.bp
+++ b/Android.bp
@@ -28,6 +28,7 @@
         "-Wno-string-compare",
         "-Wno-unused-parameter",
     ],
+    stl: "none",
 
     local_include_dirs: ["lib", "src"],