Minor fixes and improvements in makefiles
Merge commit '9eb001222e6a70459e9b1c5fc166769705f80887'
Split 'platform/aoaa_board/' into commit 'e702e8ba89bb443e48d197c8ef52cdecd4b8f250'

git-subtree-dir: platform/aoaa_board
git-subtree-mainline: 08014d00e44991ddb9ca569ca711f695b6786c16
git-subtree-split: e702e8ba89bb443e48d197c8ef52cdecd4b8f250