am 7c7f28e7: Merge changes Ib1d950e1,I3d020a3c,Ic9594718

* commit '7c7f28e71044ca04d368dec626faba37fe74818d':
  Add 2nd arch directories for apps
  Set up rules to build prebuilts for TARGET_2ND_ARCH
  Set up rules to build packages for TARGET_2ND_ARCH