Set libunwind's STL to none. am: 9724d2448e am: 697523f2c1 am: 279c2c4c35
am: 12a8cea75d

Change-Id: I8ea91a3c64200f5ab9b66f1e8b33157973f6c62d
diff --git a/Android.bp b/Android.bp
index 538476a..f4653de 100644
--- a/Android.bp
+++ b/Android.bp
@@ -102,6 +102,7 @@
     name: "libunwind",
     defaults: ["libunwind_defaults"],
     sdk_version: "21",
+    stl: "none",
 
     srcs: [
         "src/mi/init.c",