Define _LIBUNWIND_IS_NATIVE_ONLY when building LLVM libunwind. am: 4b1bd5d680 am: f458efcac7 am: a855893207

Original change: https://android-review.googlesource.com/c/platform/external/libunwind_llvm/+/1537465

MUST ONLY BE SUBMITTED BY AUTOMERGER

Change-Id: I21828a14e0d6472e19fbb38f270a917db3b8728c
diff --git a/Android.bp b/Android.bp
index b97ee0d..69ff739 100644
--- a/Android.bp
+++ b/Android.bp
@@ -36,6 +36,7 @@
     "-Wall",
     "-Werror",
     "-D_LIBUNWIND_USE_DLADDR=0",
+    "-D_LIBUNWIND_IS_NATIVE_ONLY",
 ]
 
 LIBUNWIND_CPPFLAGS = [