Android Wear N Preview 2 (NVD83H)
Switch libunwind_llvm over to building for NDK 21.

It would be preferable if this could build for API level 9, but it
depends on dl_iterate_phdr(), which only appears in API level 21 for
ARM.

Change-Id: I769a3ee19bf4a07cd75987251f2708b1f293407c
1 file changed