(1) checkout updated LTP tree under external/ltp
(2) configure LTP tree:
	cd external/ltp; make autotools; ./configure; cd -
(3) regenerate Android.ltp.mk from configured LTP tree:
	tools/regen_android_mk.sh
(4) perform a build with -k flag to keep building
    regardless of failure
(5) filter Android.mk modules (example with bullhead):
    python tools/filter_success_build.py --android_build_top=../../../../master/ --ltp_dir=../ --target_product=bullhead