add otatools-package target

Add a target to zip up all the otatools and releasetools, for easy
copying to the OTA builder machine.

Change-Id: If14b4afefcc1a20ea19dfca3f3b9f9fae73189a6
(cherry picked from commit f22b0f43efbc16c548692dc239a387edda15d78f)
1 file changed